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arXiv · 2502.17256

Low-dispersive phase-modulated rapid scanning interferometry

Fabian Richter·Ulrich Bangert·Friedemann Landmesser·Nicolai Gölz·Felix Riedel·Lukas Bruder
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Abstract

Time-domain interferometry is an important principle in Fourier transform (FT) and nonlinear femto- to attosecond spectroscopy. To optimize the resolution and sensitivity of this approach, various interferometer stabilization schemes have been developed. Among them, acousto-optical phase modulation (AOPM) of the interferometer arms combined with phase-synchronous lock-in detection has proven as a particular sensitive technique. However, the acousto-optical modulators (AOMs), required for this technique, introduce several disadvantages. Here, we demonstrate an alternative phase modulation scheme which omits AOMs, termed PM scheme here. As a benchmark, we directly compare the performance between the PM and the AOPM scheme in a linear FT spectroscopy experiment and find comparable sensitivity in both approaches.

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Fabian Richter, Ulrich Bangert, Friedemann Landmesser, Nicolai Gölz, Felix Riedel, Lukas Bruder. 2025-02-24. Low-dispersive phase-modulated rapid scanning interferometry. https://doi.org/10.1364/ol.560625

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