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

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

Workshop; Bristol Quantum Information Technologies Workshop (Virtual); 2020

University of Bristol

A very promising result from optical quantum metrology is the ability to achieve sub shot noise precision in transmission/absorptionmeasurements. This is due to the significantly lower uncertainty in light intensity of quantum beams with respect to their classicalcounterparts. In this work, we simulate results obtained when using a time multiplexed single photon source [1] to measure thetransmission of a sample, considering all experimental losses.The single photon source is based on photon pairs generated by spontaneous parametric down conversion (with CW pumping) and asubsequent time multiplexing set-up based on a binary division strategy. This enables the synchronization of the output photon with anexternal 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, thatunder certain conditions, there is no need for number resolving detectors, and on the other hand, that it works in a very low light regime,enabling minimum interaction with the sample.