Robust Weak Measurements with Certified Single Photons

Abstract

Since their introduction, weak measurements and weak values have served as a cornerstone for investigating quantum measurement theory, as well as a significant tool for quantum metrology and sensing. Here, it is shown how (anomalous) weak values can be reliably obtained with single quantum systems even without averaging over multiple experimental runs, thanks to a measurement protocol dubbed robust weak measurement. Specifically, robust weak measurements are exploited to extract the weak value of the polarization of heralded single photons, certifying the true single-particle, nonclassical nature of weak values.