Hermitian conjugate measurement

Abstract

We propose a new class of probabilistic reversing operations on the state of a system that was disturbed by a weak measurement. It can approximately recover the original state from the disturbed state especially with an additional information gain using the Hermitian conjugate of the measurement operator. We illustrate the general scheme by considering a quantum measurement consisting of spin systems with an experimentally feasible interaction and show that the reversing operation simultaneously increases both the fidelity to the original state and the information gain with such a high probability of success that their average values increase simultaneously.

26 pages, 4 figures; a paragraph is added in the introduction

References in corpus (4)

• Undoing a weak quantum measurement of a solid-state qubit
• Uncollapsing of a quantum state in a superconducting phase qubit
• Global information balance in quantum measurements
• Probabilistic reversing operation with fidelity and purity gain for macroscopic quantum superposition

Cited by in corpus (7)

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• Information, fidelity, and reversibility in single-qubit measurements
• Information, fidelity, and reversibility in general quantum measurements
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• Information and fidelity in projective measurements
• Allowed region and optimal measurement for information versus disturbance in quantum measurements
• Derivative of the disturbance with respect to information from quantum measurements