An acousto-optic modulator based bi-frequency interferometer for quantum technology

TL;DR

This paper presents a high-performance acousto-optic modulator based bi-frequency interferometer capable of quantum-level interference with high visibility and efficiency, actively stabilized for versatile quantum technology applications.

Contribution

Introduces a novel AOM-based bi-frequency interferometer with active phase stabilization and multiple quantum technology applications.

Findings

Visibility of 99.5% with 0.2% error

Optical efficiency of 95% with 1% error

Successful demonstration of quantum applications like frequency tuning and optical switching

Abstract

We demonstrate a high performance AOM based bi-frequency interferometer, which can realize either beating or beating free interference for single photon level quantum state. Visibility and optical efficiency of the interferometer are (99.5 +- 0.2)% and (95 +- 1)%, respectively. The phase of the interferometer is actively stabilized by using dithering phase locking scheme, where the phase dithering is realized by directly driving the AOMs with specially designed electronic signal. We further demonstrate applications of the interferometer in quantum technology, including bi-frequency coherent combination, frequency tuning and optical switching. These result show the interferometer is a versatile device for multiple quantum technologies.