Real-world Quantum Sensors: Evaluating Resources for Precision Measurement

TL;DR

This paper critically examines how quantum resources improve measurement precision in optical interferometry, highlighting the importance of appropriate performance measures and providing benchmarks for real-world quantum sensor experiments.

Contribution

It analyzes various performance measures for quantum-enhanced parameter estimation and recommends the most accurate methods for real-world experimental evaluation.

Findings

Some common measures overestimate quantum advantage.

Preferred analysis methods are identified for realistic experiments.

Benchmark values for experimental parameters are provided.

Abstract

Quantum physics holds the promise of enabling certain tasks with better performance than possible when only classical resources are employed. The quantum phenomena present in many experiments signify nonclassical behavior, but do not always imply superior performance. Quantifying the enhancement achieved from quantum behavior requires careful analysis of the resources involved. We analyze the specific case of parameter estimation using an optical interferometer, where increased precision can be achieved using quantum probe states. Common performance measures are examined and it is shown that some overestimate the improvement. For the simplest experimental case we compare the different measures and show this overestimate explicitly. We give the preferred analysis of real-world experiments and calculate benchmark values for experimental parameters necessary to realize a precision enhancement.