Optical parametric amplification of phase-stable terahertz-to-mid-infrared pulses studied in the time domain
Abstract
We report optical parametric amplification (OPA) of low-frequency infrared pulses in the intermediate region between terahertz (THz) frequency and mid-infrared (MIR), i.e., from 16.9 to 44.8 THz (6.7–17.8 μm). The 255-fs laser output of the Yb:KGW regenerative amplifier is compressed to 11-fs pulses using a multi-plate broadening scheme, which generates THz-to-MIR pulses with a spectrum extending to approximately 50 THz by intra-pulse differential frequency generation (DFG) in GaSe. The THz-to-MIR pulses are further amplified using a two-stage OPA in GaSe. The temporal dynamics and photocarrier effects during OPA are characterized in the time domain. Owing to the intra-pulse DFG, the long-term phase drift of the THz-to-MIR pulses after two-stage OPA is as small as 16 mrad during a 6-h operation without any active feedback. Our scheme using the intra-pulse DFG and post-amplification proposes a new route to intense THz-to-MIR light sources with extreme phase stability.
- Publication:
-
Optics Express
- Pub Date:
- February 2021
- DOI:
- 10.1364/OE.413200
- arXiv:
- arXiv:2005.03538
- Bibcode:
- 2021OExpr..29.3479K
- Keywords:
-
- Physics - Optics
- E-Print:
- Optics Express 29(3), 3479-3489 (2021)