Lecture 6 Fiber Optical Communication Lecture 6, Slide 1

Save this PDF as:

Size: px
Start display at page:

Download "Lecture 6 Fiber Optical Communication Lecture 6, Slide 1"

Transcription

1 Lecture 6 Optical transmitters Photon processes in light matter interaction Lasers Lasing conditions The rate equations CW operation Modulation response Noise Light emitting diodes (LED) Power Modulation response Bandwidth Fiber Optical Communication Lecture 6, Slide 1

2 LEDs and lasers Light-emitting diode (LED): Based on spontaneous emission Incoherent light Linewidth Δν 10 THz (Δλ = nm) Slow response time Much larger linewidth than data rate dispersive limitations Laser: Based on stimulated emission Highly coherent light Linewidth Δν = MHz Fast response time Usually much smaller linewidth than data rate Fiber Optical Communication Lecture 6, Slide 2

3 Photon processes in light matter interaction (3.1.1) Spontaneous emission Absorption Stimulated emission The emitted photon has energy hν E g E g is the bandgap energy Non-radiative recombination Reduces the number of electron-hole pairs (a) Material defects (b) Auger recombination Energy given to another electron (as kinetic energy) Fiber Optical Communication Lecture 6, Slide 3

4 Semiconductor lasers (3.1.3) Semiconductor lasers use stimulated emission: Coherent light (narrow spectrum, less pulse broadening in fibers) High output power (> 10 mw) Reduced beam divergence, high coupling efficiency (30 70%) High modulation bandwidth Principle: (up to 25 gain GHz) medium in a resonator (Fabry-Perot c Principle: A gain medium with feedback (Fabry- Perot cavity) Optical gain requires population inversion Cannot occur in thermal equilibrium coherent light The gain has a nearly linear dependence on N above N t N is the injected carrier density N t is the transparency density value partially reflecting mirrors (usually cleaved semiconductor facets) R 1 pump R 2 (current) gain medium L power gain: G = exp(gz), where g = gain coefficent Fiber Optical Communication Lecture 6, Slide 4 coherent light

5 In a heterostructure junction The heterostructure junction Stimulated emission occurs where the bandgap is lower Gain is increased by the increasing carrier density Light is confined to Light the region emission where in a the forward index of biased refraction heterostructure is higher pn-junction Direct bandgap is required AlGaAs, λ = μm InGaAsP λ = μm Si is not used n-type electrons higher bandgap material thin ( 0.1 m) lower bandgap material p-type conduction band h = hc/ E g valence band higher bandgap material mode profile distance Fiber Optical Communication Lecture 6, Slide 5

6 The power reflectivity R of an air-semiconductor interface is Usually R 1 = R 2 = R The electric field in the cavity is g is the power gain, α is the power losses Factor of two because this is amplitude, not power After one round-trip, we have E Lasing conditions (3.1.4) The limiting condition for lasing is that and this gives us the laser threshold E z E exp jz t z n 1 R n 1 Fiber Optical Communication Lecture 6, Slide 6 0 g 2 z L E R R exp j z 2Lt z 2L g Both an amplitude and a phase condition for lasing 1 1 ln 2L R R 1 2 E( z 2L) E( z) L m g 2 2

7 Longitudinal modes and the Fabry-Perot laser (3.1.5) The phase condition can be written ν m are the lasing longitudinal modes Simplest kind of semiconductor laser: A Fabry-Perot laser Uses a Fabry-Perot interferometer Will lase in several modes simultaneously Gives problems with dispersion mc 2nL Mode frequency spacing is Δν GHz for a typical laser m loss longitudinal modes dominant mode (highest gain) gain profile m-x Fiber Optical Communication Lecture 6, Slide 7 m m+x GHz for a typical laser A Fabry-Perot laser oscillates in several modes simultaneously

8 Single-mode lasers (3.2) Wavelength-dependent cavity loss single-mode lasing loss profile gain profile longitudinal modes lasing mode Distributed feedback (DFB) laser (most common) Wavelength-selective grating in the cavity Can be temperature tunable (5 nm) External-cavity laser Uses a frequency-selective element outside the cavity Widely tunable (50 nm), narrow linewidth Vertical-cavity surface-emitting laser (VCSEL) Light output orthogonal to substrate easier to produce Very good alternative to an LED Fiber Optical Communication Lecture 6, Slide 8

9 The rate equations (3.3.1) Describe the static and dynamic behavior of semiconductor lasers The number of photons is P The number of electrons is N Assuming a (transverse and longitudinal) single-mode laser dp P dn I N GP R GP sp dt dt q c p Stimulated emission Spontaneous emission into lasing mode The net rate of stimulated emission is Related to the rate of spontaneous emission n sp is around 2 for semiconductor lasers The photon lifetime is Photon loss rate Electron supply by pumping Spontaneous emission G GN N R n G sp sp p v g Stimulated emission N ln 2L R R 1 2 Fiber Optical Communication Lecture 6, Slide 9

10 CW (steady-state) operation In steady-state, time differentiation yields zero ( d/dt = 0 ) Neglect spontaneous emission for simplicity (R sp = 0) Use the rate equations to get I c For small currents: G p 1, P 0, N q 1 At lasing threshold: G p 1, P 0, N Nth N0, I Ith GN p p Above threshold: G p 1, P I Ith, N Nth const, I I q N th N P th qn c th G th G I th I Fiber Optical Communication Lecture 6, Slide 10

11 P I curves The output power from one facet, assuming equal facet reflectivity R, is P e 1 2 v g mir hp 1 2 v g 1 ln L 1 hp R Two types of degradation with increasing temperature Threshold current increases P I curves bend when injected current is increased The reasons are: Increased non-radiative recombination Increasing internal losses Fiber Optical Communication Lecture 6, Slide 11

12 Modulation bandwidth (3.3.2) The response to current modulation is obtained from the rate equations Two phenomena must be accounted for The gain has a power-dependence (decreases with optical power) The refractive index is changed due to gain/population changes In general, the rate equations must be solved numerically An analytic solution can be obtained for small-signal modulation Modulation current << I b I th Variables are linearized around the bias point For example, the power is modeled P( t) Pb pm sin( mt m) The transfer function is obtained The power transfer function is called modulation response Measured and calculated modulation response in a DFB laser Fiber Optical Communication Lecture 6, Slide 12

13 Noise in semiconductor lasers The carrier and photon numbers fluctuate The generation process is quantized The main source of noise is spontaneous emission The phase of the noise is random Perturbs both the phase and the amplitude Gives rise to a finite SNR The spectral width 0 Limited coherence Fiber Optical Communication Lecture 6, Slide 13

14 Relative intensity noise (RIN) (3.3.3) We define the power fluctuation according to The RIN spectrum is the power spectral density (PSD) of δp normalized to the square of the mean power Obtained from the rate equations with added noise terms Peaked close to the relaxation oscillation frequency This is introduced using the auto-correlation of δp Use Wiener Khinchin s theorem P( t) P( t) P( t) C pp ( ) P( t) P( t ) P( t) 2 RIN( ) The SNR is mean power/rms noise C SNR = [C pp (0)] 1/2 Obtained as 1/(integral of PSD) pp Typically db ( ) e i d Fiber Optical Communication Lecture 6, Slide 14

15 The LED output power is Light emitting diodes (LEDs) (3.5) η ext is external quantum efficiency Fraction of photons that escape the device, 1 5% η int is internal quantum efficiency Fraction of carriers that recombine radiatively, 50% I is injected current Benefits: Simple fabrication, low cost, reliable, small temperature dependence Drawbacks: P e η ext Low power, low coupling efficiency to fiber (< 10%), large spectral width, smaller modulation bandwidth η int hν q I Fiber Optical Communication Lecture 6, Slide 15

16 LED CW operation (3.5.1) Left: Output power is first proportional to the injected current......but the curve bends at higher currents......because of increasing internal losses Internal quantum efficiency also decreases with increasing temperature Right: The emitted spectrum for a 1.3 μm InGaAsP LED The spectrum is wide, nm Only suitable for short distance communication Fiber Optical Communication Lecture 6, Slide 16

17 LED modulation response (3.5.2) The rate equation for an LED contains no stimulated emission Assume a sinusoidal modulation The carrier modulation is obtained cib cim N t q q 1 We obtain the 3-dB bandwidth Limited by the carrier lifetime Typical value is MHz I dn dt I q N t I I exp j t b m exp j t f 3dB c 1 j 3 2 c m c m m Fiber Optical Communication Lecture 6, Slide 17

18 LED structures (3.5.3) Surface emitting Low cost Easy manufacturing Poor coupling to fiber Edge emitting Built-in waveguide Directivity Improved coupling Higher bandwidth (200 MHz) Fiber Optical Communication Lecture 6, Slide 18

19 Source fiber coupling (3.6.1) The coupling efficiency varies significantly < 1% for butt-coupled surface-emitting LED > 90% for lens-coupled laser to SM fiber Transmitter package often contains photo diode Will monitor the power level......and provide feedback for power control Semiconductor lasers are sensitive to optical feedback Often an optical isolator is used Temperature stabilization may be necessary Can use thermo-electric cooler Cost is often dictated by the package, not the laser itself Fiber Optical Communication Lecture 6, Slide 19

20 Dense wavelength division multiplexing transmitters Uses the ITU-T wavelength grid with spacing of 100/50/25 GHz Active wavelength locking is needed Tunable lasers are attractive Left: Package with wavelength stabilization Right: Wavelength selectable transmitter using monolithic array of lasers covering 160 nm Fiber Optical Communication Lecture 6, Slide 20

Lecture 4 Fiber Optical Communication Lecture 4, Slide 1

Lecture 4 Fiber Optical Communication Lecture 4, Slide 1 Lecture 4 Optical transmitters Photon processes in light matter interaction Lasers Lasing conditions The rate equations CW operation Modulation response Noise Light emitting diodes (LED) Power Modulation

More information

Basic concepts. Optical Sources (b) Optical Sources (a) Requirements for light sources (b) Requirements for light sources (a)

Basic concepts. Optical Sources (b) Optical Sources (a) Requirements for light sources (b) Requirements for light sources (a) Optical Sources (a) Optical Sources (b) The main light sources used with fibre optic systems are: Light-emitting diodes (LEDs) Semiconductor lasers (diode lasers) Fibre laser and other compact solid-state

More information

Introduction Fundamentals of laser Types of lasers Semiconductor lasers

Introduction Fundamentals of laser Types of lasers Semiconductor lasers ECE 5368 Introduction Fundamentals of laser Types of lasers Semiconductor lasers Introduction Fundamentals of laser Types of lasers Semiconductor lasers How many types of lasers? Many many depending on

More information

Figure 1. Schematic diagram of a Fabry-Perot laser.

Figure 1. Schematic diagram of a Fabry-Perot laser. Figure 1. Schematic diagram of a Fabry-Perot laser. Figure 1. Shows the structure of a typical edge-emitting laser. The dimensions of the active region are 200 m m in length, 2-10 m m lateral width and

More information

LASER Transmitters 1 OBJECTIVE 2 PRE-LAB

LASER Transmitters 1 OBJECTIVE 2 PRE-LAB LASER Transmitters 1 OBJECTIVE Investigate the L-I curves and spectrum of a FP Laser and observe the effects of different cavity characteristics. Learn to perform parameter sweeps in OptiSystem. 2 PRE-LAB

More information

Luminous Equivalent of Radiation

Luminous Equivalent of Radiation Intensity vs λ Luminous Equivalent of Radiation When the spectral power (p(λ) for GaP-ZnO diode has a peak at 0.69µm) is combined with the eye-sensitivity curve a peak response at 0.65µm is obtained with

More information

S Optical Networks Course Lecture 2: Essential Building Blocks

S Optical Networks Course Lecture 2: Essential Building Blocks S-72.3340 Optical Networks Course Lecture 2: Essential Building Blocks Edward Mutafungwa Communications Laboratory, Helsinki University of Technology, P. O. Box 2300, FIN-02015 TKK, Finland Tel: +358 9

More information

Optodevice Data Book ODE I. Rev.9 Mar Opnext Japan, Inc.

Optodevice Data Book ODE I. Rev.9 Mar Opnext Japan, Inc. Optodevice Data Book ODE-408-001I Rev.9 Mar. 2003 Opnext Japan, Inc. Section 1 Operating Principles 1.1 Operating Principles of Laser Diodes (LDs) and Infrared Emitting Diodes (IREDs) 1.1.1 Emitting Principles

More information

R. J. Jones Optical Sciences OPTI 511L Fall 2017

R. J. Jones Optical Sciences OPTI 511L Fall 2017 R. J. Jones Optical Sciences OPTI 511L Fall 2017 Semiconductor Lasers (2 weeks) Semiconductor (diode) lasers are by far the most widely used lasers today. Their small size and properties of the light output

More information

Semiconductor Optical Communication Components and Devices Lecture 18: Introduction to Diode Lasers - I

Semiconductor Optical Communication Components and Devices Lecture 18: Introduction to Diode Lasers - I Semiconductor Optical Communication Components and Devices Lecture 18: Introduction to Diode Lasers - I Prof. Utpal Das Professor, Department of lectrical ngineering, Laser Technology Program, Indian Institute

More information

Review of Semiconductor Physics

Review of Semiconductor Physics Review of Semiconductor Physics k B 1.38 u 10 23 JK -1 a) Energy level diagrams showing the excitation of an electron from the valence band to the conduction band. The resultant free electron can freely

More information

Semiconductor Lasers Semiconductors were originally pumped by lasers or e-beams First diode types developed in 1962: Create a pn junction in

Semiconductor Lasers Semiconductors were originally pumped by lasers or e-beams First diode types developed in 1962: Create a pn junction in Semiconductor Lasers Semiconductors were originally pumped by lasers or e-beams First diode types developed in 1962: Create a pn junction in semiconductor material Pumped now with high current density

More information

Ph 77 ADVANCED PHYSICS LABORATORY ATOMIC AND OPTICAL PHYSICS

Ph 77 ADVANCED PHYSICS LABORATORY ATOMIC AND OPTICAL PHYSICS Ph 77 ADVANCED PHYSICS LABORATORY ATOMIC AND OPTICAL PHYSICS Diode Laser Characteristics I. BACKGROUND Beginning in the mid 1960 s, before the development of semiconductor diode lasers, physicists mostly

More information

Light Sources, Modulation, Transmitters and Receivers

Light Sources, Modulation, Transmitters and Receivers Optical Fibres and Telecommunications Light Sources, Modulation, Transmitters and Receivers Introduction Previous section looked at Fibres. How is light generated in the first place? How is light modulated?

More information

LASER DIODE MODULATION AND NOISE

LASER DIODE MODULATION AND NOISE > 5' O ft I o Vi LASER DIODE MODULATION AND NOISE K. Petermann lnstitutfiir Hochfrequenztechnik, Technische Universitdt Berlin Kluwer Academic Publishers i Dordrecht / Boston / London KTK Scientific Publishers

More information

White Paper Laser Sources For Optical Transceivers. Giacomo Losio ProLabs Head of Technology

White Paper Laser Sources For Optical Transceivers. Giacomo Losio ProLabs Head of Technology White Paper Laser Sources For Optical Transceivers Giacomo Losio ProLabs Head of Technology September 2014 Laser Sources For Optical Transceivers Optical transceivers use different semiconductor laser

More information

FIBER OPTICS. Prof. R.K. Shevgaonkar. Department of Electrical Engineering. Indian Institute of Technology, Bombay. Lecture: 18.

FIBER OPTICS. Prof. R.K. Shevgaonkar. Department of Electrical Engineering. Indian Institute of Technology, Bombay. Lecture: 18. FIBER OPTICS Prof. R.K. Shevgaonkar Department of Electrical Engineering Indian Institute of Technology, Bombay Lecture: 18 Optical Sources- Introduction to LASER Diodes Fiber Optics, Prof. R.K. Shevgaonkar,

More information

Laser Diode. Photonic Network By Dr. M H Zaidi

Laser Diode. Photonic Network By Dr. M H Zaidi Laser Diode Light emitters are a key element in any fiber optic system. This component converts the electrical signal into a corresponding light signal that can be injected into the fiber. The light emitter

More information

Lasers PH 645/ OSE 645/ EE 613 Summer 2010 Section 1: T/Th 2:45-4:45 PM Engineering Building 240

Lasers PH 645/ OSE 645/ EE 613 Summer 2010 Section 1: T/Th 2:45-4:45 PM Engineering Building 240 Lasers PH 645/ OSE 645/ EE 613 Summer 2010 Section 1: T/Th 2:45-4:45 PM Engineering Building 240 John D. Williams, Ph.D. Department of Electrical and Computer Engineering 406 Optics Building - UAHuntsville,

More information

Chapter 4 O t p ica c l a So S u o r u ce c s

Chapter 4 O t p ica c l a So S u o r u ce c s Chapter 4 Optical Sources Contents Review of Semiconductor Physics Light Emitting Diode (LED) - Structure, Material,Quantum efficiency, LED Power, Modulation Laser Diodes - structure, Modes, Rate Equation,Quantum

More information

Semiconductor Lasers Semiconductors were originally pumped by lasers or e-beams First diode types developed in 1962: Create a pn junction in

Semiconductor Lasers Semiconductors were originally pumped by lasers or e-beams First diode types developed in 1962: Create a pn junction in Semiconductor Lasers Semiconductors were originally pumped by lasers or e-beams First diode types developed in 1962: Create a pn junction in semiconductor material Pumped now with high current density

More information

VERTICAL CAVITY SURFACE EMITTING LASER

VERTICAL CAVITY SURFACE EMITTING LASER VERTICAL CAVITY SURFACE EMITTING LASER Nandhavel International University Bremen 1/14 Outline Laser action, optical cavity (Fabry Perot, DBR and DBF) What is VCSEL? How does VCSEL work? How is it different

More information

TECHNICAL BRIEF O K I L A S E R D I O D E P R O D U C T S. OKI Laser Diodes

TECHNICAL BRIEF O K I L A S E R D I O D E P R O D U C T S. OKI Laser Diodes TECHNICAL BRIEF O K I L A S E R D I O D E P R O D U C T S OKI Laser Diodes June 1995 OKI Laser Diodes INTRODUCTION This technical brief presents an overview of OKI laser diode and edge emitting light emitting

More information

ECE 340 Lecture 29 : LEDs and Lasers Class Outline:

ECE 340 Lecture 29 : LEDs and Lasers Class Outline: ECE 340 Lecture 29 : LEDs and Lasers Class Outline: Light Emitting Diodes Lasers Semiconductor Lasers Things you should know when you leave Key Questions What is an LED and how does it work? How does a

More information

Chapter 1 Introduction

Chapter 1 Introduction Chapter 1 Introduction 1-1 Preface Telecommunication lasers have evolved substantially since the introduction of the early AlGaAs-based semiconductor lasers in the late 1970s suitable for transmitting

More information

Key Questions. What is an LED and how does it work? How does a laser work? How does a semiconductor laser work? ECE 340 Lecture 29 : LEDs and Lasers

Key Questions. What is an LED and how does it work? How does a laser work? How does a semiconductor laser work? ECE 340 Lecture 29 : LEDs and Lasers Things you should know when you leave Key Questions ECE 340 Lecture 29 : LEDs and Class Outline: What is an LED and how does it How does a laser How does a semiconductor laser How do light emitting diodes

More information

Lecture 9 External Modulators and Detectors

Lecture 9 External Modulators and Detectors Optical Fibres and Telecommunications Lecture 9 External Modulators and Detectors Introduction Where are we? A look at some real laser diodes. External modulators Mach-Zender Electro-absorption modulators

More information

Application Instruction 002. Superluminescent Light Emitting Diodes: Device Fundamentals and Reliability

Application Instruction 002. Superluminescent Light Emitting Diodes: Device Fundamentals and Reliability I. Introduction II. III. IV. SLED Fundamentals SLED Temperature Performance SLED and Optical Feedback V. Operation Stability, Reliability and Life VI. Summary InPhenix, Inc., 25 N. Mines Road, Livermore,

More information

Examination Optoelectronic Communication Technology. April 11, Name: Student ID number: OCT1 1: OCT 2: OCT 3: OCT 4: Total: Grade:

Examination Optoelectronic Communication Technology. April 11, Name: Student ID number: OCT1 1: OCT 2: OCT 3: OCT 4: Total: Grade: Examination Optoelectronic Communication Technology April, 26 Name: Student ID number: OCT : OCT 2: OCT 3: OCT 4: Total: Grade: Declaration of Consent I hereby agree to have my exam results published on

More information

Optoelectronics ELEC-E3210

Optoelectronics ELEC-E3210 Optoelectronics ELEC-E3210 Lecture 4 Spring 2016 Outline 1 Lateral confinement: index and gain guiding 2 Surface emitting lasers 3 DFB, DBR, and C3 lasers 4 Quantum well lasers 5 Mode locking P. Bhattacharya:

More information

ECEN689: Special Topics in Optical Interconnects Circuits and Systems Spring 2016

ECEN689: Special Topics in Optical Interconnects Circuits and Systems Spring 2016 ECEN689: Special Topics in Optical Interconnects Circuits and Systems Spring 016 Lecture 7: Transmitter Analysis Sam Palermo Analog & Mixed-Signal Center Texas A&M University Optical Modulation Techniques

More information

BN 1000 May Profile Optische Systeme GmbH Gauss Str. 11 D Karlsfeld / Germany. Tel Fax

BN 1000 May Profile Optische Systeme GmbH Gauss Str. 11 D Karlsfeld / Germany. Tel Fax BN 1000 May 2000 Profile Optische Systeme GmbH Gauss Str. 11 D - 85757 Karlsfeld / Germany Tel + 49 8131 5956-0 Fax + 49 8131 5956-99 info@profile-optsys.com www.profile-optsys.com Profile Inc. 87 Hibernia

More information

EE 230: Optical Fiber Communication Transmitters

EE 230: Optical Fiber Communication Transmitters EE 230: Optical Fiber Communication Transmitters From the movie Warriors of the Net Laser Diode Structures Most require multiple growth steps Thermal cycling is problematic for electronic devices Fabry

More information

Optical Amplifiers (Chapter 6)

Optical Amplifiers (Chapter 6) Optical Amplifiers (Chapter 6) General optical amplifier theory Semiconductor Optical Amplifier (SOA) Raman Amplifiers Erbium-doped Fiber Amplifiers (EDFA) Read Chapter 6, pp. 226-266 Loss & dispersion

More information

Modulation of light. Direct modulation of sources Electro-absorption (EA) modulators

Modulation of light. Direct modulation of sources Electro-absorption (EA) modulators Modulation of light Direct modulation of sources Electro-absorption (EA) modulators Why Modulation A communication link is established by transmission of information reliably Optical modulation is embedding

More information

MAHALAKSHMI ENGINEERING COLLEGE TIRUCHIRAPALLI

MAHALAKSHMI ENGINEERING COLLEGE TIRUCHIRAPALLI MAHALAKSHMI ENGINEERING COLLEGE TIRUCHIRAPALLI - 621213 DEPARTMENT : ECE SUBJECT NAME : OPTICAL COMMUNICATION & NETWORKS SUBJECT CODE : EC 2402 UNIT III: SOURCES AND DETECTORS PART -A (2 Marks) 1. What

More information

VCSELs and Optical Interconnects

VCSELs and Optical Interconnects VCSELs and Optical Interconnects Anders Larsson Chalmers University of Technology ADOPT Winter School on Optics and Photonics February 4-7, 6 Outline Part VCSEL basics - Physics and design - Static and

More information

A continuous-wave Raman silicon laser

A continuous-wave Raman silicon laser A continuous-wave Raman silicon laser Haisheng Rong, Richard Jones,.. - Intel Corporation Ultrafast Terahertz nanoelectronics Lab Jae-seok Kim 1 Contents 1. Abstract 2. Background I. Raman scattering II.

More information

Optical MEMS in Compound Semiconductors Advanced Engineering Materials, Cal Poly, SLO November 16, 2007

Optical MEMS in Compound Semiconductors Advanced Engineering Materials, Cal Poly, SLO November 16, 2007 Optical MEMS in Compound Semiconductors Advanced Engineering Materials, Cal Poly, SLO November 16, 2007 Outline Brief Motivation Optical Processes in Semiconductors Reflectors and Optical Cavities Diode

More information

Doppler-Free Spetroscopy of Rubidium

Doppler-Free Spetroscopy of Rubidium Doppler-Free Spetroscopy of Rubidium Pranjal Vachaspati, Sabrina Pasterski MIT Department of Physics (Dated: April 17, 2013) We present a technique for spectroscopy of rubidium that eliminates doppler

More information

Wavelength Control and Locking with Sub-MHz Precision

Wavelength Control and Locking with Sub-MHz Precision Wavelength Control and Locking with Sub-MHz Precision A PZT actuator on one of the resonator mirrors enables the Verdi output wavelength to be rapidly tuned over a range of several GHz or tightly locked

More information

High brightness semiconductor lasers M.L. Osowski, W. Hu, R.M. Lammert, T. Liu, Y. Ma, S.W. Oh, C. Panja, P.T. Rudy, T. Stakelon and J.E.

High brightness semiconductor lasers M.L. Osowski, W. Hu, R.M. Lammert, T. Liu, Y. Ma, S.W. Oh, C. Panja, P.T. Rudy, T. Stakelon and J.E. QPC Lasers, Inc. 2007 SPIE Photonics West Paper: Mon Jan 22, 2007, 1:20 pm, LASE Conference 6456, Session 3 High brightness semiconductor lasers M.L. Osowski, W. Hu, R.M. Lammert, T. Liu, Y. Ma, S.W. Oh,

More information

NEW YORK CITY COLLEGE of TECHNOLOGY

NEW YORK CITY COLLEGE of TECHNOLOGY NEW YORK CITY COLLEGE of TECHNOLOGY THE CITY UNIVERSITY OF NEW YORK DEPARTMENT OF ELECTRICAL AND TELECOMMUNICATIONS ENGINEERING TECHNOLOGY Course : TCET 4102 (TC 700) Fiber-optic communications Module

More information

Chapter 3 OPTICAL SOURCES AND DETECTORS

Chapter 3 OPTICAL SOURCES AND DETECTORS Chapter 3 OPTICAL SOURCES AND DETECTORS 3. Optical sources and Detectors 3.1 Introduction: The success of light wave communications and optical fiber sensors is due to the result of two technological breakthroughs.

More information

Understanding Optical Communications

Understanding Optical Communications Understanding Optical Communications Harry J. R. Dutton International Technical Support Organization http://www.redbooks.ibm.com SG24-5230-00 International Technical Support Organization Understanding

More information

Vertical External Cavity Surface Emitting Laser

Vertical External Cavity Surface Emitting Laser Chapter 4 Optical-pumped Vertical External Cavity Surface Emitting Laser The booming laser techniques named VECSEL combine the flexibility of semiconductor band structure and advantages of solid-state

More information

Optical Amplifiers. Continued. Photonic Network By Dr. M H Zaidi

Optical Amplifiers. Continued. Photonic Network By Dr. M H Zaidi Optical Amplifiers Continued EDFA Multi Stage Designs 1st Active Stage Co-pumped 2nd Active Stage Counter-pumped Input Signal Er 3+ Doped Fiber Er 3+ Doped Fiber Output Signal Optical Isolator Optical

More information

Optoelectronics EE/OPE 451, OPT 444 Fall 2009 Section 1: T/Th 9:30-10:55 PM

Optoelectronics EE/OPE 451, OPT 444 Fall 2009 Section 1: T/Th 9:30-10:55 PM Optoelectronics EE/OPE 451, OPT 444 Fall 009 Section 1: T/Th 9:30-10:55 PM John D. Williams, Ph.D. Department of Electrical and Computer Engineering 406 Optics Building - UAHuntsville, Huntsville, AL 35899

More information

Advanced Optical Communications Prof. R. K. Shevgaonkar Department of Electrical Engineering Indian Institute of Technology, Bombay

Advanced Optical Communications Prof. R. K. Shevgaonkar Department of Electrical Engineering Indian Institute of Technology, Bombay Advanced Optical Communications Prof. R. K. Shevgaonkar Department of Electrical Engineering Indian Institute of Technology, Bombay Lecture No. # 27 EDFA In the last lecture, we talked about wavelength

More information

Lecture 4 INTEGRATED PHOTONICS

Lecture 4 INTEGRATED PHOTONICS Lecture 4 INTEGRATED PHOTONICS What is photonics? Photonic applications use the photon in the same way that electronic applications use the electron. Devices that run on light have a number of advantages

More information

Lecture 1: Course Overview. Rajeev J. Ram

Lecture 1: Course Overview. Rajeev J. Ram Lecture 1: Course Overview Rajeev J. Ram Office: 36-491 Telephone: X3-4182 Email: rajeev@mit.edu Syllabus Basic concepts Advanced concepts Background: p-n junctions Photodetectors Modulators Optical amplifiers

More information

High-frequency tuning of high-powered DFB MOPA system with diffraction limited power up to 1.5W

High-frequency tuning of high-powered DFB MOPA system with diffraction limited power up to 1.5W High-frequency tuning of high-powered DFB MOPA system with diffraction limited power up to 1.5W Joachim Sacher, Richard Knispel, Sandra Stry Sacher Lasertechnik GmbH, Hannah Arendt Str. 3-7, D-3537 Marburg,

More information

Wavelength switching using multicavity semiconductor laser diodes

Wavelength switching using multicavity semiconductor laser diodes Wavelength switching using multicavity semiconductor laser diodes A. P. Kanjamala and A. F. J. Levi Department of Electrical Engineering University of Southern California Los Angeles, California 989-1111

More information

PERFORMANCE OF PHOTODIGM S DBR SEMICONDUCTOR LASERS FOR PICOSECOND AND NANOSECOND PULSING APPLICATIONS

PERFORMANCE OF PHOTODIGM S DBR SEMICONDUCTOR LASERS FOR PICOSECOND AND NANOSECOND PULSING APPLICATIONS PERFORMANCE OF PHOTODIGM S DBR SEMICONDUCTOR LASERS FOR PICOSECOND AND NANOSECOND PULSING APPLICATIONS By Jason O Daniel, Ph.D. TABLE OF CONTENTS 1. Introduction...1 2. Pulse Measurements for Pulse Widths

More information

Synchronization in Chaotic Vertical-Cavity Surface-Emitting Semiconductor Lasers

Synchronization in Chaotic Vertical-Cavity Surface-Emitting Semiconductor Lasers Synchronization in Chaotic Vertical-Cavity Surface-Emitting Semiconductor Lasers Natsuki Fujiwara and Junji Ohtsubo Faculty of Engineering, Shizuoka University, 3-5-1 Johoku, Hamamatsu, 432-8561 Japan

More information

MASSACHUSETTS INSTITUTE OF TECHNOLOGY Department of Electrical Engineering and Computer Science

MASSACHUSETTS INSTITUTE OF TECHNOLOGY Department of Electrical Engineering and Computer Science Student Name Date MASSACHUSETTS INSTITUTE OF TECHNOLOGY Department of Electrical Engineering and Computer Science 6.161 Modern Optics Project Laboratory Laboratory Exercise No. 6 Fall 2010 Solid-State

More information

Optical Sources and Detectors

Optical Sources and Detectors Optical Sources and Detectors 1. Optical Sources Optical transmitter coverts electrical input signal into corresponding optical signal. The optical signal is then launched into the fiber. Optical source

More information

Optical Fibers p. 1 Basic Concepts p. 1 Step-Index Fibers p. 2 Graded-Index Fibers p. 4 Design and Fabrication p. 6 Silica Fibers p.

Optical Fibers p. 1 Basic Concepts p. 1 Step-Index Fibers p. 2 Graded-Index Fibers p. 4 Design and Fabrication p. 6 Silica Fibers p. Preface p. xiii Optical Fibers p. 1 Basic Concepts p. 1 Step-Index Fibers p. 2 Graded-Index Fibers p. 4 Design and Fabrication p. 6 Silica Fibers p. 6 Plastic Optical Fibers p. 9 Microstructure Optical

More information

Optical Amplifiers Photonics and Integrated Optics (ELEC-E3240) Zhipei Sun Photonics Group Department of Micro- and Nanosciences Aalto University

Optical Amplifiers Photonics and Integrated Optics (ELEC-E3240) Zhipei Sun Photonics Group Department of Micro- and Nanosciences Aalto University Photonics Group Department of Micro- and Nanosciences Aalto University Optical Amplifiers Photonics and Integrated Optics (ELEC-E3240) Zhipei Sun Last Lecture Topics Course introduction Ray optics & optical

More information

Lecture 18: Photodetectors

Lecture 18: Photodetectors Lecture 18: Photodetectors Contents 1 Introduction 1 2 Photodetector principle 2 3 Photoconductor 4 4 Photodiodes 6 4.1 Heterojunction photodiode.................... 8 4.2 Metal-semiconductor photodiode................

More information

To generate a broadband light source by using mutually injection-locked Fabry-Perot laser diodes

To generate a broadband light source by using mutually injection-locked Fabry-Perot laser diodes To generate a broadband light source by using mutually injection-locked Fabry-Perot laser diodes Cheng-Ling Ying 1, Yu-Chieh Chi 2, Chia-Chin Tsai 3, Chien-Pen Chuang 3, and Hai-Han Lu 2a) 1 Department

More information

UNIT-III SOURCES AND DETECTORS. According to the shape of the band gap as a function of the momentum, semiconductors are classified as

UNIT-III SOURCES AND DETECTORS. According to the shape of the band gap as a function of the momentum, semiconductors are classified as UNIT-III SOURCES AND DETECTORS DIRECT AND INDIRECT BAND GAP SEMICONDUCTORS: According to the shape of the band gap as a function of the momentum, semiconductors are classified as 1. Direct band gap semiconductors

More information

Optical Sources & Detectors for Fiber Optic communication

Optical Sources & Detectors for Fiber Optic communication Optical Sources & Detectors for Fiber Optic communication JK Chhabra EX Scientist, CSIO, Chandigarh Professor ECE JIET Jind Consultants Professor IIIT Allahabad chhabra_ jk@yahoo.com The Nobel Prize in

More information

PARAMETER SYMBOL UNITS MIN TYP MAX TEST CONDITIONS Emission wavelength λ R nm 762,5 763,7 T=25 C, I TEC

PARAMETER SYMBOL UNITS MIN TYP MAX TEST CONDITIONS Emission wavelength λ R nm 762,5 763,7 T=25 C, I TEC Single Mode VCSEL 763nm TO5 & TEC Vertical Cavity Surface-Emitting Laser internal TEC and Thermistor Narrow linewidth > 2nm tunability with TEC High performance and reliability ELECTRO-OPTICAL CHARACTERISTICS

More information

Temporal coherence characteristics of a superluminescent diode system with an optical feedback mechanism

Temporal coherence characteristics of a superluminescent diode system with an optical feedback mechanism VI Temporal coherence characteristics of a superluminescent diode system with an optical feedback mechanism Fang-Wen Sheu and Pei-Ling Luo Department of Applied Physics, National Chiayi University, Chiayi

More information

RECENTLY, studies have begun that are designed to meet

RECENTLY, studies have begun that are designed to meet 838 IEEE JOURNAL OF QUANTUM ELECTRONICS, VOL. 43, NO. 9, SEPTEMBER 2007 Design of a Fiber Bragg Grating External Cavity Diode Laser to Realize Mode-Hop Isolation Toshiya Sato Abstract Recently, a unique

More information

Semiconductor Optical Active Devices for Photonic Networks

Semiconductor Optical Active Devices for Photonic Networks UDC 621.375.8:621.38:621.391.6 Semiconductor Optical Active Devices for Photonic Networks VKiyohide Wakao VHaruhisa Soda VYuji Kotaki (Manuscript received January 28, 1999) This paper describes recent

More information

Functional Materials. Optoelectronic devices

Functional Materials. Optoelectronic devices Functional Materials Lecture 2: Optoelectronic materials and devices (inorganic). Photonic materials Optoelectronic devices Light-emitting diode (LED) displays Photodiode and Solar cell Photoconductive

More information

SEMICONDUCTOR lasers and amplifiers are important

SEMICONDUCTOR lasers and amplifiers are important 240 JOURNAL OF LIGHTWAVE TECHNOLOGY, VOL. 28, NO. 3, FEBRUARY 1, 2010 Temperature-Dependent Saturation Characteristics of Injection Seeded Fabry Pérot Laser Diodes/Reflective Optical Amplifiers Hongyun

More information

Single-Frequency, 2-cm, Yb-Doped Silica-Fiber Laser

Single-Frequency, 2-cm, Yb-Doped Silica-Fiber Laser Single-Frequency, 2-cm, Yb-Doped Silica-Fiber Laser W. Guan and J. R. Marciante University of Rochester Laboratory for Laser Energetics The Institute of Optics Frontiers in Optics 2006 90th OSA Annual

More information

Lecture 2. Introduction to Optical. Ivan Avrutsky, ECE 5870 Optical Communication Networks, Lecture 2. Slide 1

Lecture 2. Introduction to Optical. Ivan Avrutsky, ECE 5870 Optical Communication Networks, Lecture 2. Slide 1 Lecture 2 Introduction to Optical Networks Ivan Avrutsky, ECE 5870 Optical Communication Networks, Lecture 2 Slide 1 Optical Communication Networks 1. Why optical? 2. How does it work? 3. How to design

More information

Degradation analysis in asymmetric sampled grating distributed feedback laser diodes

Degradation analysis in asymmetric sampled grating distributed feedback laser diodes Microelectronics Journal 8 (7) 74 74 www.elsevier.com/locate/mejo Degradation analysis in asymmetric sampled grating distributed feedback laser diodes Han Sung Joo, Sang-Wan Ryu, Jeha Kim, Ilgu Yun Semiconductor

More information

visibility values: 1) V1=0.5 2) V2=0.9 3) V3=0.99 b) In the three cases considered, what are the values of FSR (Free Spectral Range) and

visibility values: 1) V1=0.5 2) V2=0.9 3) V3=0.99 b) In the three cases considered, what are the values of FSR (Free Spectral Range) and EXERCISES OF OPTICAL MEASUREMENTS BY ENRICO RANDONE AND CESARE SVELTO EXERCISE 1 A CW laser radiation (λ=2.1 µm) is delivered to a Fabry-Pérot interferometer made of 2 identical plane and parallel mirrors

More information

High-power semiconductor lasers for applications requiring GHz linewidth source

High-power semiconductor lasers for applications requiring GHz linewidth source High-power semiconductor lasers for applications requiring GHz linewidth source Ivan Divliansky* a, Vadim Smirnov b, George Venus a, Alex Gourevitch a, Leonid Glebov a a CREOL/The College of Optics and

More information

Investigation of InGaAsP/InP DFB and FP Laser Diodes Noise Characteristic

Investigation of InGaAsP/InP DFB and FP Laser Diodes Noise Characteristic ISSN 9 MATERIALS SCIENCE (MEDŽIAGOTYRA). Vol., No. 4. 4 Investigation of InGaAsP/InP DFB and FP Laser Diodes Noise Characteristic Jonas MATUKAS, Vilius PALENSKIS, Sandra PRALGAUSKAITĖ, Emilis ŠERMUKŠNIS

More information

IST IP NOBEL "Next generation Optical network for Broadband European Leadership"

IST IP NOBEL Next generation Optical network for Broadband European Leadership DBR Tunable Lasers A variation of the DFB laser is the distributed Bragg reflector (DBR) laser. It operates in a similar manner except that the grating, instead of being etched into the gain medium, is

More information

Elements of Optical Networking

Elements of Optical Networking Bruckner Elements of Optical Networking Basics and practice of optical data communication With 217 Figures, 13 Tables and 93 Exercises Translated by Patricia Joliet VIEWEG+ TEUBNER VII Content Preface

More information

Optical Transmission Fundamentals

Optical Transmission Fundamentals Optical Transmission Fundamentals F. Vasey, CERN-EP-ESE Context Technology HEP Specifics 12 Nov 2018 0 Context: Bandwidth Demand Internet traffic is growing at ~Moore s law Global interconnection bandwidth

More information

CONTENTS. Chapter 1 Wave Nature of Light 19

CONTENTS. Chapter 1 Wave Nature of Light 19 CONTENTS Chapter 1 Wave Nature of Light 19 1.1 Light Waves in a Homogeneous Medium 19 A. Plane Electromagnetic Wave 19 B. Maxwell's Wave Equation and Diverging Waves 22 Example 1.1.1 A diverging laser

More information

Notes on Optical Amplifiers

Notes on Optical Amplifiers Notes on Optical Amplifiers Optical amplifiers typically use energy transitions such as those in atomic media or electron/hole recombination in semiconductors. In optical amplifiers that use semiconductor

More information

Ultralow-power all-optical RAM based on nanocavities

Ultralow-power all-optical RAM based on nanocavities Supplementary information SUPPLEMENTARY INFORMATION Ultralow-power all-optical RAM based on nanocavities Kengo Nozaki, Akihiko Shinya, Shinji Matsuo, Yasumasa Suzaki, Toru Segawa, Tomonari Sato, Yoshihiro

More information

Simultaneous Measurements for Tunable Laser Source Linewidth with Homodyne Detection

Simultaneous Measurements for Tunable Laser Source Linewidth with Homodyne Detection Simultaneous Measurements for Tunable Laser Source Linewidth with Homodyne Detection Adnan H. Ali Technical college / Baghdad- Iraq Tel: 96-4-770-794-8995 E-mail: Adnan_h_ali@yahoo.com Received: April

More information

Physics of Waveguide Photodetectors with Integrated Amplification

Physics of Waveguide Photodetectors with Integrated Amplification Physics of Waveguide Photodetectors with Integrated Amplification J. Piprek, D. Lasaosa, D. Pasquariello, and J. E. Bowers Electrical and Computer Engineering Department University of California, Santa

More information

AIR FORCE INSTITUTE OF TECHNOLOGY

AIR FORCE INSTITUTE OF TECHNOLOGY CHARACTERIZATION AND DYNAMIC ANALYSIS OF LONG-CAVITY MULTI-SECTION GAIN-LEVERED QUANTUM-DOT LASERS THESIS John R. Schmidt, Second Lieutenant, USAF AFIT-ENG-13-M-45 DEPARTMENT OF THE AIR FORCE AIR UNIVERSITY

More information

Design of External Cavity Semiconductor Lasers to Suppress Wavelength Shift and Mode Hopping

Design of External Cavity Semiconductor Lasers to Suppress Wavelength Shift and Mode Hopping ST/03/055/PM Design o External Cavity Semiconductor Lasers to Suppress Wavelength Shit and Mode Hopping L. Zhao and Z. P. Fang Abstract In this report, a model o ernal cavity semiconductor laser is built,

More information

High-Speed Directly Modulated Lasers

High-Speed Directly Modulated Lasers High-Speed Directly Modulated Lasers Tsuyoshi Yamamoto Fujitsu Laboratories Ltd. Some parts of the results in this presentation belong to Next-generation High-efficiency Network Device Project, which Photonics

More information

VCSELs With Enhanced Single-Mode Power and Stabilized Polarization for Oxygen Sensing

VCSELs With Enhanced Single-Mode Power and Stabilized Polarization for Oxygen Sensing VCSELs With Enhanced Single-Mode Power and Stabilized Polarization for Oxygen Sensing Fernando Rinaldi and Johannes Michael Ostermann Vertical-cavity surface-emitting lasers (VCSELs) with single-mode,

More information

Swept Wavelength Testing:

Swept Wavelength Testing: Application Note 13 Swept Wavelength Testing: Characterizing the Tuning Linearity of Tunable Laser Sources In a swept-wavelength measurement system, the wavelength of a tunable laser source (TLS) is swept

More information

Chapter 8. Digital Links

Chapter 8. Digital Links Chapter 8 Digital Links Point-to-point Links Link Power Budget Rise-time Budget Power Penalties Dispersions Noise Content Photonic Digital Link Analysis & Design Point-to-Point Link Requirement: - Data

More information

SUPPLEMENTARY INFORMATION

SUPPLEMENTARY INFORMATION Room-temperature InP distributed feedback laser array directly grown on silicon Zhechao Wang, Bin Tian, Marianna Pantouvaki, Weiming Guo, Philippe Absil, Joris Van Campenhout, Clement Merckling and Dries

More information

Spatial Investigation of Transverse Mode Turn-On Dynamics in VCSELs

Spatial Investigation of Transverse Mode Turn-On Dynamics in VCSELs Spatial Investigation of Transverse Mode Turn-On Dynamics in VCSELs Safwat W.Z. Mahmoud Data transmission experiments with single-mode as well as multimode 85 nm VCSELs are carried out from a near-field

More information

Novel Dual-mode locking semiconductor laser for millimetre-wave generation

Novel Dual-mode locking semiconductor laser for millimetre-wave generation Novel Dual-mode locking semiconductor laser for millimetre-wave generation P. Acedo 1, C. Roda 1, H. Lamela 1, G. Carpintero 1, J.P. Vilcot 2, S. Garidel 2 1 Grupo de Optoelectrónica y Tecnología Láser,

More information

A Narrow-Band Tunable Diode Laser System with Grating Feedback

A Narrow-Band Tunable Diode Laser System with Grating Feedback A Narrow-Band Tunable Diode Laser System with Grating Feedback S.P. Spirydovich Draft Abstract The description of diode laser was presented. The tuning laser system was built and aligned. The free run

More information

Safa O. Kasap Electrical Engineering Department, University of Saskatchewan, Saskatoon, S7N 5A9, Canada

Safa O. Kasap Electrical Engineering Department, University of Saskatchewan, Saskatoon, S7N 5A9, Canada 1 Optoelectronics Safa O. Kasap Electrical Engineering Department, University of Saskatchewan, Saskatoon, S7N 5A9, Canada e-mail: kasap@engr.usask.ca Abstract It is useful to view today s optoelectronics

More information

Highly Reliable 40-mW 25-GHz 20-ch Thermally Tunable DFB Laser Module, Integrated with Wavelength Monitor

Highly Reliable 40-mW 25-GHz 20-ch Thermally Tunable DFB Laser Module, Integrated with Wavelength Monitor Highly Reliable 4-mW 2-GHz 2-ch Thermally Tunable DFB Laser Module, Integrated with Wavelength Monitor by Tatsuya Kimoto *, Tatsushi Shinagawa *, Toshikazu Mukaihara *, Hideyuki Nasu *, Shuichi Tamura

More information

21. (i) Briefly explain the evolution of fiber optic system (ii) Compare the configuration of different types of fibers. or 22. (b)(i) Derive modal eq

21. (i) Briefly explain the evolution of fiber optic system (ii) Compare the configuration of different types of fibers. or 22. (b)(i) Derive modal eq Unit-1 Part-A FATIMA MICHAEL COLLEGE OF ENGINEERING & TECHNOLOGY Senkottai Village, Madurai Sivagangai Main Road, Madurai - 625 020. [An ISO 9001:2008 Certified Institution] DEPARTMENT OF ELECTRONICS AND

More information

Lecture 8 Fiber Optical Communication Lecture 8, Slide 1

Lecture 8 Fiber Optical Communication Lecture 8, Slide 1 Lecture 8 Bit error rate The Q value Receiver sensitivity Sensitivity degradation Extinction ratio RIN Timing jitter Chirp Forward error correction Fiber Optical Communication Lecture 8, Slide Bit error

More information

Lecture 7 Fiber Optical Communication Lecture 7, Slide 1

Lecture 7 Fiber Optical Communication Lecture 7, Slide 1 Dispersion management Lecture 7 Dispersion compensating fibers (DCF) Fiber Bragg gratings (FBG) Dispersion-equalizing filters Optical phase conjugation (OPC) Electronic dispersion compensation (EDC) Fiber

More information

Low Noise High Power Ultra-Stable Diode Pumped Er-Yb Phosphate Glass Laser

Low Noise High Power Ultra-Stable Diode Pumped Er-Yb Phosphate Glass Laser Low Noise High Power Ultra-Stable Diode Pumped Er-Yb Phosphate Glass Laser R. van Leeuwen, B. Xu, L. S. Watkins, Q. Wang, and C. Ghosh Princeton Optronics, Inc., 1 Electronics Drive, Mercerville, NJ 8619

More information

DIODE LASER SPECTROSCOPY (160309)

DIODE LASER SPECTROSCOPY (160309) DIODE LASER SPECTROSCOPY (160309) Introduction The purpose of this laboratory exercise is to illustrate how we may investigate tiny energy splittings in an atomic system using laser spectroscopy. As an

More information