Using technical noise to increase the signal-to-noise ratio, via imaginary weak values

TL;DR

This paper explores how imaginary weak values in quantum measurements can leverage technical noise to improve the signal-to-noise ratio, supported by numerical analysis and relevant to quantum metrology.

Contribution

It demonstrates that random variations in the measurement device's initial state can be advantageous when using imaginary weak values, enhancing precision.

Findings

Random initial states can improve measurement precision with imaginary weak values.

Numerical calculations support the benefit of using imaginary weak values.

The approach explains noise reduction observed in recent experiments.

Abstract

The advantages of weak measurements, and especially measurements of imaginary weak values, for precision enhancement, are discussed. A situation is considered in which the initial state of the measurement device varies randomly on each run, and is shown to be in fact beneficial when imaginary weak values are used. The result is supported by numerical calculation and also provides an explanation for the reduction of technical noise in some recent experimental results. A connection to quantum metrology formalism is made.