Negation of photon loss provided by negative weak value

TL;DR

This paper demonstrates how negative weak values can be used to negate photon loss in quantum processes, providing a novel method for controlling quantum system losses.

Contribution

It introduces a new application of negative weak values to counteract photon loss, extending weak measurement techniques beyond conventional conditions.

Findings

Negative weak value of -1 can completely negate photon loss.

Experimental validation of photon loss negation using weak values.

Demonstrates non-unitary quantum process control.

Abstract

We propose a usage of a weak value for a quantum processing between preselection and postselection. While the weak value of a projector of 1 provides a process with certainty like the probability of 1, the weak value of -1 negates the process completely. Their mutually opposite effect is approved without a conventional `weak' condition. In addition the quantum process is not limited to be unitary; in particular we consider a loss of photons and experimentally demonstrate the negation of the photon loss by using the negative weak value of -1 against the positive weak value of 1.