Sub shot noise transmission measurement scheme using a time multiplexing single photon source

MIGUEL A. LAROTONDA; LAURA T. KNOLL; AGUSTINA G. MAGNONI

Bristol (evento online)

Workshop; Bristol Quantum Technology Workshop; 2020

University of Bristol

A very promising result from optical quantum metrology is the ability to achieve sub shot noise variance in transmission/absorption measurements. This is due to the significantly lower uncertainty in light intensity of quantum beams with respect to their classical counterparts. In this work, we simulate results from an experiment that uses a multiplexed single photon source [1] in this kind of measurements, considering all the experimental losses.The single photon source is based on pair generation by spontaneous parametric down conversion (with CW pumping) and a subsequent time multiplexing set-up based on a binary division strategy. This enables the synchronization of the output photon with an external clock signal at the same time that increases the single photon probability of the source. The subpoissonian statistics of theoutput signal is the key for achieving sub shot noise performance. Two remarkable features of this proposal are, on the one hand, that there is no need for number resolving detectors, and on the other hand, that it works in a very low light regime, enabling minimum disruption on the measurement of biological or other fragile samples.