Asymmetric high energy dual optical parametric amplifier for parametric processes and waveform synthesis

TL;DR

This paper presents an asymmetric high-energy dual optical parametric amplifier capable of phase locking multiple wavelengths with high power and tunability, enabling advanced waveform synthesis and terahertz generation.

Contribution

The work introduces a novel high-energy dual OPA with phase locking at incommensurate wavelengths, high tunability, and potential for strong pump DFG and waveform synthesis.

Findings

Idlers and signals phase locked within 200 mrad rms

Generated 3.5 mJ and 1.5 mJ outputs in high and low energy arms

Demonstrated terahertz generation via waveform synthesis in air plasma

Abstract

We report on an asymmetric high energy dual optical parametric amplifier (OPA) which is capable of having either the idlers, signals, or depleted pumps, relatively phase locked at commensurate or incommensurate wavelengths. Idlers and signals can be locked on the order of 200 mrad rms or better, corresponding to a 212 as jitter at $\lambda$=2$\mu$m. The high energy arm of the OPA outputs a combined 3.5 mJ of signal and idler, while the low energy arm outputs 1.5 mJ, with the entire system being pumped with a 1 kHz, 18 mJ Ti:Sapphire laser. Both arms are independently tunable from 1080 nm-2600 nm. The combination of relative phase locking, high output power and peak intensity, and large tunability makes our OPA an ideal tool for use in difference frequency generation (DFG) in the strong pump regime, and for high peak field waveform synthesis in the near-infrared. To demonstrate this ability we generate terahertz radiation through two color waveform synthesis in air plasma and show the influence of the relative phase on the generated terahertz intensity. The ability to phase lock multiple incommensurate wavelengths at high energies opens the door to a multitude of possibilities of strong pump DFG and waveform synthesis.