New generation Laser amplifier system for FEL applications at DESY.

New generation Laser amplifier system for FEL applications at DESY. Franz Tavella Helmholtz-Institut-Jena Merging advanced solid-state Laser technology with FEL sources Helmholtz-Institut-Jena DESY F. Tavella Hamburg 26-01-2012 Page 1

Overview. Novel Laser amplifiers systems at DESY applications requirements and Laser specifications The system Development status OPCPA and it s pump amplifier system. development methods enabling technologies outlook F. Tavella Hamburg 26-01-2012 Page 2

Laser amplifier applications at FELs. Electron gun photo-injector Laser LINAC (electron accelerator) (the mother of all Lasers) Optical seed laser and HHG Undulator section accelerator FLASH II experimental hall (Pump probe lasers) F. Tavella Hamburg 26-01-2012 Page 3

The seeding driving laser amplifier. Laser Seed X-ray ɳ Rep.-rate P ave Comments EEHG 0.8 m 100 GW >10 fsec (mj) 200 nm up to GW 2 nm >10-1 conv., 10% losses 1 MHz (burst) 100s W for burst UV and IR both required CEP (evt.) HGHG 0.8 m 10 GW >10 fsec (100 J) 200 nm 100 MW 20 nm >10-1 conv., 10% losses 1 MHz (burst) 100s W for burst CEP stabilization for ultrafast pulses HHG+ HGHG or EEHG 0.8 m 100 GW 10 fsec (mj) 20 nm 100 kw 1 nm 10-5 conv., 10% losses 1 MHz (burst) kw same HHG 0.8 m 100 GW 10-30 fsec (>1 mj) >10 nm 100 kw > 10 nm 10-5 conv., 10% losses 1 MHz (burst) kw 100 khz development ongoing HHG 0.8 m 1 TW <10 fsec (>10 mj) <10 nm 1 MW <10 nm 10-6 conv., 10% losses 1 MHz (burst) 10s kw extreme R&D necessary F. Tavella Hamburg 26-01-2012 Page 4

Special needs input from the future user community. Pulse energy few mj 800 µs Burst repetition rate 100 khz 1 MHz continuous 100 khz operation possible.. 100 ms t Pulse duration (tunable?) 10-30 fs seeding up to hundreds of W average power <7 fs pump/probe Laser CEP stabilization? synchronization precision to the FEL <10 fs 24/7 operation NIR Laser amplifier (~650-1000 nm) F. Tavella Hamburg 26-01-2012 Page 5

Optical Parametric Chirped Pulse Amplification (OPCPA). Non-collinear amplification (NOPA) type-i phasematching in BBO pump wave: extraordinary axis signal / idler wave: ordinary axis Dubietis et al., Opt. Commun., 88, 437 (1992). I. N. Ross et al., Opt. Commun., 144, 125 (1997). k pump = k signal + k idler Optical parametric chirped pulse amplification broadband amplification instantaneous process no energy storage, no inversion negligible absorption, no thermal load High repetition rates (high average power) conversion efficiency >20% in 2-pass OPCPA but requires a non-conventional pump amplifier! F. Tavella Hamburg 26-01-2012 Page 6

Optical Parametric Chirped Pulse Amplifier: Setup. Laser system Setup: combining OPCPA with ultra-short pump amplifiers - Ti:Sa oscillator frontend split for signal and pump seed - adaptive dispersion control for signal (4-f SLM) - Yb based CPA with high repetition rate - sub-ps pump pulses from CPA F. Tavella Hamburg 26-01-2012 Page 7

The OPCPA pump amplifier. F. Tavella Hamburg 26-01-2012 Page 8

The OPCPA pump amplifier. The challenge: OPCPA pump Laser central wavelength: 1030 nm (SHG @ 515 nm used for OPCPA) pulse energy: 20 mj 10 mj @ 515 nm repetition rate: 100 khz cw / burst (1 MHz final version) pulse duration: sub-1 ps multi-kw average power Laser amplifier! F. Tavella Hamburg 26-01-2012 Page 9

Pump amplifier: fiber amplifier front-end. 4 fiber amplifiers (2 Yb:glass rod type PCF amplifier) Chirped Pulse Amplifier (CPA), 2 ns 1 ps current amplifier max 50 W continuous and burst repetition rate (100 khz 1 MHz) T. Eidam, et al, Opt. Lett. 35, 94-96, (2010). Fiber amplifier (IAP Jena) Helmholtz-Institute Jena F. Tavella Hamburg 26-01-2012 Page 10

Pump amplifier: fiber amplifier front-end. fiber amplifier T. Eidam, et al, Opt. Lett. 35, 94-96, (2010). Fiber amplifier (IAP Jena) Helmholtz-Institute Jena stretcher/compressor F. Tavella Hamburg 26-01-2012 Page 11

Results: OPCPA with fiber pump laser. 1-Stage OPCPA 20 µj, 6.9 fs (F. Tavella et al, Opt. Exp. 18 4689-4694 (2010) 2-Stage OPCPA with CEP stabilization 70 µj, 8.0 fs J. Rothhardt et al, Opt. Exp. 18 12719-12726 (2010) 2-stage OPCPA with optimized adaptive dispersion control 87 µj, 4.8 fs S. Hädrich et al, Opt. Letters 36, 3 (2011) F. Tavella Hamburg 26-01-2012 Page 12

Pump amplifier: Innoslab fiber amplifier amplifier. front-end. T. Eidam, et al, Opt. Lett. 35, 94-96, (2010). Fiber amplifier (IAP Jena) Helmholtz-Institute Jena Innoslab amplifier (ILT Aachen) F. Tavella Hamburg 26-01-2012 Page 13

Pump amplifier: Innoslab amplifier. Development from Amphos (spin-off from ILT) Different sets of amplifier modules >1.5 kw currently installed at DESY (burst-mode and continuous operation possible) up to multi-kw burst mode planned XFEL/DESY Innoslab amplifier (ILT Aachen) F. Tavella Hamburg 26-01-2012 Page 14

Pump amplifier: Thin-disk amplifier. Trumpf Laser GmbH Multipass design with max. 30 passes through the disk Thin disk multipass amplifier (DESY) F. Tavella Hamburg 26-01-2012 Page 16

Pump amplifier: Thin-disk amplifier. Trumpf Laser GmbH Multipass design with max. 30 passes through the disk Thin disk multipass amplifier (DESY) F. Tavella Hamburg 26-01-2012 Page 17

Burst energy [J] AC signal [arb.] Burst energy [J] Pulse energy [mj] Pump amplifier: Thin-disk amplifier. 3.5 3.0 2.5 30 2.0 1.5 1.0 25 20 15 10 0.5 5 0 0,0 0,2 0,4 0,6 0,8 Time [ms] 0.0 0 2 4 6 8 10 12 14 16 Pump energy [J] 2,0 Thin disk multipass amplifier (DESY) 1,5 1,0 1,0 0,8 0,6 energy increase to max. 44.5 mj / pulse but asymmetric burst amplification factor of 118 (1.17 per pass) 0,5 0,4 0,2 1.1 % rms stability 0,0-2 -1 0 1 2 0,0 0 10 20 30 40 Time [min] Delay [ps] flat burst at 25 mj amplified pulse energy compressed to 820 fs F. Tavella Hamburg 26-01-2012 Page 18

Pump amplifier The challenge: OPCPA pump Laser central wavelength: 1030 nm (SHG @ 515 nm used for OPCPA) pulse energy: 20 mj 10 mj @ 515 nm repetition rate: 100 khz cw / burst (1 MHz final version) pulse duration: sub-1 ps OPCPA development F. Tavella Hamburg 26-01-2012 Page 19

what can we do next? Ep >1 mj tp = 5-30 fs 0.1-1 MHz > 5 W 100s of W multi kw F. Tavella Hamburg 26-01-2012 Page 20

what can we do next? Ep >1 mj tp = 5-30 fs 0.1-1 MHz ambitious project for the next years 10 Hz operation 400 μj 20 mj several 100 mj (1 J possible?) Ep > 40 mj tp = <7 fs 10 Hz F. Tavella Hamburg 26-01-2012 Page 21

The Laser-Express. OPCPA kilowatt-burst pump amplifier next step is OPCPA ready to be used this year Franz Tavella Arik Willner Arvid Hage Highly efficient QPM HHG source - developement & characterization - dual gas jet target - FLASH-II seeding planned in 2015 Mark Prandolini Robert Riedel XUV SEED e- XUV Michael Schulz F. Tavella Hamburg 26-01-2012 Page 22

Seeding FLASH II. development of high repeptition rate, mj-level, sub-10 fs laser amplifiers -enabling technologies- Collaboration partners: - Helmholtz Institut Jena - Institut of Applied Physics Jena (IAP) group of A.Tünnermann - Institut für Lasertechnik Aachen (ILT) H. Hoffmann group - ILT-spinoff Amphos T. Mans, C. Schnitzler - European XFEL M. Lederer development of a laser-driven XUV source with high conversion efficiency (QPM-schemes) Collaboration partners: - Queens University of Belfast (QUB) group of M. Zepf - Technical University of Crete (TEI) group of M. Tatarakis and N. Papadogiannis Laser Development... F. Tavella, A. Willner, M. Schulz, R. Riedel, A,Hage, M. Prandolini (HI-Jena/DESY/Hamburg University) DESY-Hamburg University S. Düsterer, J. Rossbach, M. Drescher, H. Schlarb, J. Feldhaus FLASH-II team (DESY-Helmholtz Zentrum Berlin)... B. Faatz, A. Meseck, R. Mitzner, F. Tavella, A. Willner, M. Schulz, R. Riedel M. Abo-Bakr, N. Baboi, J. Bahrdt, V. Balandin, W. Decking, S. Düsterer, R. Follath, A. Gamp, K. Holldack, K. Honkavaara, T. Limberg, K. Tiedtke, R. Treusch, K. Wittenburg, S. Schreiber, M.V. Yurkov, E. Schneidmiller F. Tavella Hamburg 26-01-2012 Page 23