Single photon beat note in an acousto-optic modulator-based interferometer

Abstract

To cite this version:Renaud Mathevet, Benoît Chalopin, Sébastien Massenot. Single photon beat note in an acoustooptic modulator-based interferometer. AbstractWe present in the following a quantum optics experiment appropriate for advanced undergraduate students with former experience in quantum optics. It extends classical single photon setups to the time dependent domain. We demonstrate self-heterodyning of heralded single photons using a Mach-Zender like interferometer where beamsplitters are replaced by two acousto-optic modulators (AOMs). The single photon beat note is recorded over time at the frequency difference between the RF generators driving the AOMs, which makes it observable directly on a human time scale i. e. with periods above a fraction of a second. To compare with our observations, we tailor the standard quantum optics formalism for beam splitters to take into account the frequency shifts associated with the AOMs.

Acousto-optic modulator-based bi-frequency interferometer for quantum technology

“…[13] is only about 15%, far from the ideal value of 1. Moreover, both experiments make use of co-propagation optical configuration and create either slow beating of about 1 kHz [13] or a fast beating signal of about 200 MHz [17] . On one hand, this co-propagation setup and scanning effect of beating signal will reduce the influence of phase drifting and make active phase stabilizing less important.…”

“…The visibility of the beating signal in Ref. [13] is only about 15%, far from the ideal value of 1. Moreover, both experiments make use of co-propagation optical configuration and create either slow beating of about 1 kHz [13] or a fast beating signal of about 200 MHz [17] .…”

“…As shown in Fig. 1(a), without loss of generality, we assume two optical fields, âω 1 and bω 2 , are aligned to the −1 st and the 1 st order Bragg diffraction of an AOM, and the output fields ĉ and d have the form of [13] ĉ = t bω2 e iθ râ ω1−Ω ,…”

“…Taking advantage of switching with high isolation, they have been used in photon subtraction-based non-Gaussian state generation [7,8] , photon-triggered homodyne tomography [9] , or controlling of quantum memory [10] . Taking advantage of introducing frequency shifting to an optical field, they are used to implement optical heterodyning [11,12] , to observe a beating signal from single photons [13] , or to generate a phase-locking reference without displacing the quantum state [14] . Currently, the maximum diffraction efficiency of commercially available AOMs is around 85%, which reduces as the bandwidth of AOM increases, and a harsh requirement on the input beam size and driving power has to be fulfilled in order to achieve this efficiency.…”

“…Recently, AOM has been used as a beam splitter to implement photon heterodyning [12] . More recently, AOMbased interferometers have been used to observe the beating signal of single photons [13] or bidirectional routing laser pulses [17] , where both beam-splitting and beam-combining functions are carried out by AOMs. The visibility of the beating signal in Ref.…”