Demonstration of displacement- and frequency-noise free laser interferometry using bi-directional Mach-Zehnder interferometers

TL;DR

This paper demonstrates a partial implementation of displacement- and frequency-noise free laser interferometry using bi-directional Mach-Zehnder interferometers, confirming noise cancellation capabilities and achieving a high simulated signal-to-noise ratio.

Contribution

It introduces a minimal optical configuration for DFI with bi-directional MZIs, confirming noise cancellation and performance in a practical setup.

Findings

Displacement noise was effectively canceled in the setup.

Achieved a simulated SNR of 45dB.

Confirmed the essential feature of DFI with partial implementation.

Abstract

We have demonstrated displacement- and frequency-noise free laser interferometry (DFI) by partially implementing a recently proposed optical configuration using bi-directional Mach-Zehnder interferometers (MZI). This partial implementation, the minimum necessary to be called DFI, has confirmed the essential feature of DFI: the combination of two MZI signals can be carried out in a way which cancels displacement noise of the mirrors while maintaining gravitational wave signals. The attained maximum displacement noise suppression allowed a simulated-SNR of 45dB.