English

Mixing of quantum states under Markovian dissipation and coherent control

Quantum Physics 2019-05-01 v2

Abstract

Given any two quantum states ρ\rho and σ\sigma in Hilbert spaces of equal dimension satisfying the majorization condition ρσ\rho \succ \sigma, it is always possible to transform ρσ\rho \mapsto \sigma by a unital quantum map. In fact, any such transformation can be achieved just by means of noisy operations, i.e., by access to maximally mixed ancillary states and unitary transformations that act jointly in the system-ancilla space. Here, we investigate the possible transitions between states (i.e., the induced preorder of states) when one restricts the unitary control to the quantum system alone and replaces the maximally mixed ancillas with a Markovian master equation, represented by a unital Lindbladian. As a main result, we find necessary and sufficient conditions for the Lindbladian dissipation to have the same converting power as that of noisy operations, i.e., any transformation ρσ\rho \mapsto \sigma is possible if and only if ρσ\rho \succ \sigma.

Keywords

Cite

@article{arxiv.1811.06575,
  title  = {Mixing of quantum states under Markovian dissipation and coherent control},
  author = {Georgios Styliaris and Álvaro M. Alhambra and Paolo Zanardi},
  journal= {arXiv preprint arXiv:1811.06575},
  year   = {2019}
}