Coherent Generation of Broadband Pulsed Light in the SWIR and MWIR using an All Polarization-Maintaining Fiber Frequency Comb Source H. HOOGLAND, M. ENGELBRECHT, C. McRAVEN, R. HOLZWARTH Menlo Systems, GmbH, Martinsried, Germany A. THAI, D. SÁNCHEZ, S. L. COUSIN, M. HEMMER, M. BAUDISCH ICFO - Institut de Ciències Fotòniques, Barcelona, Spain K. ZAWILSKI, P. G. SCHUNEMANN BAE Systems, Nashua, NH, USA J. BIEGERT ICREA - Instituciò Catalana de Recerca i Estudis Avançats, Barcelona, Spain.

Frequency Comb Technology Frequency Domain Single mode: 2 modes: 4 modes: 10 modes: Time Domain Laser gain bandwidth frequency Intensity Cavity longitudinal mode structure frequency Intensity frequency Intensity Laser output spectrum Figure adapted from Wikipedia, Mode-locking

Frequency comb technology

Self-referenced frequency comb Repetition rate frequency is stabilized by cavity length Offset frequency can be measured directly and stabilized by controlling cavity dispersion Phys. Rev. Lett. 84, 5102 (2000) Phys. Rev. Lett. 85, 2264 (2000)

Frequency Comb Applications Clocks – Direct RF to Optical Frequency link Stabilization for STIRAP – Weak transitions requiring high coherence Laser ranging (LIDAR) Remote chemical-sensing

Frequency Comb Applications Calibration of Spectrometers – HARPS – ~ 1 cm/s HARPS fiber A fiber B fiber A fiber B Monolithic connection Image: ESO press release 2012

Frequency Comb Applications Spectroscopy – Time-resolved (TRFCS) – MH08 – Ultrafast transient absorption – MH14 – Precision absorption – MK11, TB06, TJ05 – Dual comb – TJ03, TJ04 – Direct – RD08, TI09 – Velocity Modulation (VMS) – TG15, FA01

Spectroscopy with combs Have previously demonstrated a comb at 3 μm 2 color, 2 arm MOPA Direct production with difference frequency generation (DFG) Frequency comb direct generation limited to Yb, Er, Ti:Sapph, etc. Would like to extend to NIR and further

2.03 micron comb seed source Adapted from Opt. Express 21, (2013)

2.03 micron comb seed source Opt. Express 21, (2013) 2.03 μm 128 fs pulse width 110 mW

6.5 micron comb schematic

2 micron compressor Most materials have anamolous dispersion Martinez-type compressor Pulse lengths are 128 fs

DFG with CdSiP 2 Phase matching map CdSiP 2  Optical axis 

6.5 micron comb generation

Conclusion Broadband 2 μm seed source 100 MHz, 128 fs, 110 mW Broadband 6.5 μm comb generation using DFG in CdSiP MHz, 50 fs, 8.5 mW Thank you for listening!