High-energy burst mode thin-disk multipass amplifier

for laser Compton X-ray sourceSiva Sankar Nagisetty1,2, Michal Chyla1, Martin Smrž1, Akira Endo1 and Tomáš Mocek1

1) HiLASE Centre, Institute of Physics AS CR, v.v.i. Za Radnicí 828, Dolní Břežany 252 41, Czech Republic2) Czech Technical University in Prague, Břehová 7, Prague 115 19, Czech Republic

Laser Compton back scattering

X ray photon number

λp : peak X ray wavelength

Ne : total electron number

Np : total laser photon number

r : interaction cross section

Bea

m r

adiu

s [µ

m]

Thin disk laser development

Multipass amplifier design

PERLA B laser system

5mJ @ 10 kHz, 50 mJ/burst,

o-o eff.27%pulse duration ~1ns

High energy, short pulse 2ps, high beam quality M2<1.5 laser beam

ACKNOWLEDGMENT This poster was co financed by the European Regional development Fund and the state budget of the Czech Republic (project HiLASE CoE: Grant No. CZ.02.1.01/0.0/0.0/15_006/0000674) and by the European Union’s Horizon

2020 research and innovation programme under garnt agreement No. 739573. This work was also supported by the Ministry of Education, Youth and Sports of the Czech Republic (Programmes NPU I Project No. LO1602, Large Research Infrastructure

Project No. LM2015086), and by the Czech Science Foundation (GACR) under project No. GA16-12960S

Diamond bonded disk ROC-20m

Thickness 140 µm. Diameter 17mm

Bevel 0.1º. Doping concentration 11%

Seed energy 10mJ/10 pulses. Rep. rate 10kHz

Pump power 2kW. Rep. rate 100Hz

Pump spot 7.5mm

Pre-pumping time 350µsec

24 passes (12 reflections) on disk

Atomic Diffusion Bonding thin disk

500W and 5kW Thin disk heads

Output energy in free running mode with pulsed

pumping using 5kW thin disk head

Fiber

front-end

CFBG

stretcher

AOM pulse

picker 10kHz

Burst thin disk

regenerative

amplifier

AOM pulse

picker

10kHz@100Hz

Burst thin disk

multipass

amplifier

Grating

pulse

compressor

50 mJ

Conclusion

Non-Lasing surface temperature of soldered and

ADB disk

Burst pulse amplification in one pump pulse

Burst energy and single pass gain

dependence on No. of reflectionsSingle pass gain dependence on pump spot

fill factor (mode size/pump spot)

Thin disk multipass amplifier schematic

Mirror array

Nearly collimated seed beam propagation with in the multipass amplifier with 12 reflections on thin disk TD

PERLA B Thin disk laser system layout

Regenerative amplifier

CW 50 W, o-o eff.47%

Amplification of single pulse with in burst

Ring cavity regenerative

amplifier with two disks is under

development

FWHM 1.46 nm

central 1030.4 nm

Regenerative amplifier: Linear cavity 50 mJ/burst, Ring cavity under construction to increase the output up to 10mJ at 10kHz. Multipass amplifier design with mirror array for amplification up to 650 mJ/burst.

Simulated the multipass amplifier and tested the mirror array; awaiting thin-disk. Improvement of the code with ASE and heat distribution. Seeding the multipass amplifier with 10mJ pulses in burst and obtain

650mJ/burst