Single-cycle, 643-mW average power THz source based on tilted pulse front in lithium niobate

TL;DR

This paper reports the highest average power single-cycle THz source using optical rectification in lithium niobate, enabled by a high-power ultrafast laser, suitable for advanced nonlinear spectroscopy with reduced measurement times.

Contribution

It demonstrates the highest average power single-cycle THz source using cryogenic lithium niobate and a 500 W ultrafast laser, advancing high-power THz generation capabilities.

Findings

Achieved multi-100 mW average power at 100 kHz and 40 kHz repetition rates.

Identified optimal fluence conditions for efficient THz generation.

Benchmark for high-power THz spectroscopy systems using ultrafast Yb lasers.

Abstract

We present, to the best of our knowledge, the highest average power from a laser-driven single-cycle THz source demonstrated so far, using optical rectification in the titled pulse-front geometry in cryogenically cooled lithium niobate, pumped by a commercially available 500 W ultrafast thin-disk Yb-amplifier. We study repetition rate dependent effects in our setup at 100 kHz and 40 kHz at this high average power, revealing different optimal fluence conditions for efficient conversion. The demonstrated sources with multi-100 mW average power at these high repetition rates combine high THz pulse energies and high repetition rate and is thus ideally suited for nonlinear THz spectroscopy experiments with significantly reduced measurement times. The presented result is a first benchmark for high average power THz time domain spectroscopy systems for nonlinear spectroscopy, driven by very high average power ultrafast Yb lasers.