Photoconductive receivers at 1030 nm for high average power pulsed THz detection

TL;DR

This paper presents optimized ErAs:InAlGaAs photoconductive receivers for 1030 nm, demonstrating high dynamic range detection of high-power pulsed THz radiation suitable for advanced ultrafast laser systems.

Contribution

It introduces a new photoconductive detector optimized for 1030 nm, achieving record high dynamic range in THz detection with high average power sources.

Findings

Achieved over 115 dB dynamic range in THz detection.

Demonstrated compatibility with high-power Ytterbium-based lasers.

Identified pathways to reach 150 dB dynamic range.

Abstract

In the last few years, many advances have been made in the demonstration of high-average power pulsed THz sources; however, little effort has been made to study compatible sensitive field-resolved detectors. Here, we investigate ErAs:InAlGaAs photoconductive receivers optimized for a probe wavelength of 1030 nm and thus suitable for the new class of high-power ultrafast Ytterbium-based laser sources for THz generation and detection. The performance of the receiver is tested with a few-cycle THz source with high average power up to 20 mW and the dynamic range and saturation behavior of the receiver is thoroughly characterized. Under optimized settings, a dynamic range of more than 115 dB is reached in a 120 s measurement time with 20 mW of THz average power, which is among the highest reported values to date. By reviewing the state-of-the art in TDS measurement and post-processing technology, we identify current limitations and guidelines for further increasing the dynamic range towards 150 dB in short measurement times using high average power THz systems.