English

The effects of different quantum feedback types on the tightness of the variance-based uncertainty

Quantum Physics 2017-02-16 v1

Abstract

The effect of the quantum feedback on the tightness of the variance-based uncertainty, the possibility of using quantum feedback to prepare the state with a better tightness, and the relationship between the tightness of the uncertainty and the mixedness of the system are studied. It is found that the tightness of Schrodinger-Robertson uncertainty (SUR) relation has a strict liner relationship with the mixedness of the system. As for the Robertson uncertainty relation (RUR), we find that the tightness can be enhanced by tuning the feedback at the beginning of the evolution. In addition, we deduce that the tightness of RUR has an inverse relationship with the mixedness and the relationship turns into a strict linear one when the system reach the steady state.

Keywords

Cite

@article{arxiv.1702.04452,
  title  = {The effects of different quantum feedback types on the tightness of the variance-based uncertainty},
  author = {Xiao Zheng and Guo-Feng Zhang},
  journal= {arXiv preprint arXiv:1702.04452},
  year   = {2017}
}

Comments

13 pages,10 figures,in press