English

Information gain versus coupling strength in quantum measurements

Quantum Physics 2012-05-08 v2

Abstract

We investigate the relationship between the information gain and the interaction strength between the quantum system and the measuring device. A strategy is proposed to calculate the information gain of the measuring device as the coupling strength is a variable. For qubit systems, we prove that the information gain increases monotonically with the coupling strength. It is obtained that the information gain of the projective measurement along the x-direction reduces with the increasing of the measurement strength along the z-direction, and a complementarity of information gain in the measurements along those two directions is presented.

Keywords

Cite

@article{arxiv.1203.2251,
  title  = {Information gain versus coupling strength in quantum measurements},
  author = {Xuanmin Zhu and Yuxiang Zhang and Quanhui Liu and Shengjun Wu},
  journal= {arXiv preprint arXiv:1203.2251},
  year   = {2012}
}

Comments

7 pages, 1 figures

R2 v1 2026-06-21T20:32:06.798Z