pith. sign in

arxiv: quant-ph/0507020 · v3 · submitted 2005-07-03 · 🪐 quant-ph

Reversible quantum measurement with arbitrary spins

classification 🪐 quant-ph
keywords measurementreversingsystemfidelityreversiblearbitraryinteractionprobe
0
0 comments X
read the original abstract

We propose a physically reversible quantum measurement of an arbitrary spin-s system using a spin-j probe via an Ising interaction. In the case of a spin-1/2 system (s=1/2), we explicitly construct a reversing measurement and evaluate the degree of reversibility in terms of fidelity. The recovery of the measured state is pronounced when the probe has a high spin (j>1/2), because the fidelity changes drastically during the reversible measurement and the reversing measurement. We also show that the reversing measurement scheme for a spin-1/2 system can serve as an experimentally feasible approximate reversing measurement for a high-spin system (s>1/2). If the interaction is sufficiently weak, the reversing measurement can recover a cat state almost deterministically in spite of there being a large fidelity change.

This paper has not been read by Pith yet.

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.