Photonic Integrated Circuits for 400 Gigabit and 1 Terabit Coherent Transport

Photonic Integrated Circuits for 400 Gigabit and 1 Terabit Coherent Transport September 25, 2013

OUTLINE Overview of Optical Transport Market Evolution of Coherent Optical Module PICs for Line-Side 400G Coherent Optical Modules and Linecards Tunable Laser Integrated Coherent Transmitter (ICT) Integrated Coherent Receiver (ICR) Array of TLs, ICTs & ICRs for 400GE/1T PIC for Client-Side 400G Optical Modules 25G EML Summary 2

Overview of Optical Transport Market Evolution of Coherent Optical Module PICs for Line-Side 400G Coherent Optical Modules and Linecards Tunable Laser Integrated Coherent Transmitter (ICT) Integrated Coherent Receiver (ICR) Array of TLs, ICTs & ICRs for 400GE/1T PIC for Client-Side 400G Optical Modules 25G EML Summary 3

Optical Transport Market: 10/100/400G 300pin T-XFP 10G (ON-OFF Keying) 100G (Coherent, DSP) 400G (Coherent, DSP) Metro (Enterprise CDC /cloud/ ROADM 2~3 years 0~2 years 2~3 years 2~3 years DC) 0~2 years 2~3 years LH Metro ROADM LH XFP SFP+ Metro 2-deg LH 4-deg WSS NEM linecard Programmable C-CFP C-CFP2 C-CFP4 SDN Metro 2/4-deg 1~3 years LH 8~12 deg WSS, MCS LH Metro (Enterprise /cloud/ DC) CD-CFP T-SFP+ T-XFP T-SFP+ 168pin Enablers: PICs HOM/DSP (28/20nm CMOS) CDFP 4

Overview of Optical Transport Market Evolution of Coherent Optical Module PICs for Line-Side 400G Coherent Optical Modules and Linecards Tunable Laser Integrated Coherent Transmitter (ICT) Integrated Coherent Receiver (ICR) Array of TLs, ICTs & ICRs for 400GE/1T PIC for Client-Side 400G Optical Modules 25G EML Summary 5

Coherent Optical Module Outlook CFP2 107.5x41.5x12.4 mm None of these existing form factors have 20/40 x 10G or 8/16x 25G interfaces 5 x7 (200G MSA?) CFP (200G MSA?) 5 x7 (400G MSA?) CFP (400G MSA?) 100/150/200G 200~ 400G Module Evolution 5 x7 CFP 145x82x13.6 mm 100G Module Evolution CFP4 6

Coherent Optical Module Outlook None of these existing form factors have 20 or 40 x 10G interfaces 5 x7 (200G MSA?) CFP (200G MSA?) 5 x7 (400G MSA?) CFP (400G MSA?) 200~ 400G Module Evolution # ICT # ICR Drivers 1 (metro)/ 2 (LH) 1 (metro)/ 2 (LH) 2 (metro)/ 4 (LH) 2 (metro)/ 4 (LH) 1 (metro)/ 2 (LH) 1 (metro)/ 2 (LH) 2 (metro)/ 4 (LH) 2 (metro)/ 4 (LH) 4 linear(metro)/ 8 limiting (LH) 4 linear(metro)/ 8 limiting (LH) 8 linear(metro)/ 16 limiting (LH) 8 linear(metro)/ 16 limiting (LH) 7

Overview of Optical Transport Market Evolution of Coherent Optical Module PICs for Line-Side 400G Coherent Optical Modules and Linecards Tunable Laser Integrated Coherent Transmitter (ICT) Integrated Coherent Receiver (ICR) Array of TLs, ICTs & ICRs for 400GE/1T PIC for Client-Side 400G Optical Modules 25G EML Summary 8

Tunable Lasers for 400G/1T Gridless Tuning 400G example: 200G/λ with 35GHz spacing 1T example: 200G/λ with 40GHz spacing Narrow Linewdith Negligible OSNR penalty @ f T s < 10-5 for DP-16QAM, i.e., laser linewidth f < 300KHz. High Optical Power To compensate the low drive voltage due to linearity consideration - Allow splitting for both TX and LO - To suppress direction detection terms more effectively in a multi-channel ROADM condition Drive voltage 9

Gridless Tuning NeoPhotonics laser technology is the perfect choice for gridless tuning: Thermally tuned DFB laser is gridless by design with no modehops over the thermal gradient of each laser stripe. SOA provides shutter function for dark-tuning 10

High Tunable Laser Optical Power Use high saturation power, low-gain SOA SOA output can achieve 17.5~18dBm BOL, 16dBm EOL SOA also provides VOA function for adjusting output power level. With Neo lossless MEMS combiner, SOA gain can be very small (~5dB), OSNR > 50dB still viable. @50C Use distributed current injection inputs multi-injection laser shows approx +0.5 db of power compared to regular laser chips. Power (mw) 120 100 80 60 40 Multi-injection Regular 20 0 0 100 200 300 400 500 600 Current (ma) 11

Integrated Coherent Transmitter- Options of Integration and Packaging MZI TX Tunable Laser MZI MZI MZI 90 o LO 1. TL+ dual-i/q modulators 2. Dual I/Q modulators + drivers 3. All included 12

ICT to Support Flexible Transceiver (Ciena, ECOC 2012) 13

Intradyne Coherent Reciever Product Evolution OIF 1.1 compliant Silica PLC based High performance ipbs /L band /w power monitoring Gen 1 VICR OIF compliant Silica PLC based VOA integrated High dynamic range and low noise Gen 2 SFF ICR General OIF 1.2 (Type 2 ) Silica PLC based 33 x16 x6.5 Integrated MPD/VOA Gen 3 Dual port SFF ICR custom InP (or PLC) based Metro/LH application Multi channel 200G/400G 14

400G ICR Block Diagram ( Gen 3 ) LO#1 Signal VOA BS PBS 90 deg Hybrid 90 deg Hybrid + - + - + - + - 200G LO#2 Signal VOA BS PBS 90 deg Hybrid 90 deg Hybrid + - + - + - + - 200G 15

Array of PICs for 400GE and 1T transceivers 2, 4, 5 or 10 array TLs 2, 4, 5 or 10 array ICTs 2, 4, 5 or 10 array ICRs Challenges Power consumption management Yield loss The number of pins for control and RF interfaces Skew management in interfacing with ADC/DAC 16

Overview of Optical Transport Market Evolution of Coherent Optical Module PICs for Line-Side 400G Coherent Optical Modules and Linecards Tunable Laser Integrated Coherent Transmitter (ICT) Integrated Coherent Receiver (ICR) Array of TLs, ICTs & ICRs for 400GE/1T PIC for Client-Side 400G Optical Modules 25G EML Summary 17

400GE Client-Side: 25G EML as the key component 16x25G NRZ/OOK 8x50Gb/s PAM-4 4x100Gb/s DMT 18

Summary Need standard or MSA for 400G and 1T optical modules Otherwise, a converged 100G industry will diverge again! 400G and 1T optical modules will require PICs, array of PICs, and multi-channel driver and TIA ICs Technical challenges for optical transceiver modules include: Power consumption Yield Interface with next-gen ADC s and DAC s (pitch, skew, amplitude, etc.) Numerous pins for control and RF interfaces 19