English

Survival of entanglement in thermal states

Quantum Physics 2008-02-13 v2

Abstract

We present a general sufficiency condition for the presence of multipartite entanglement in thermal states stemming from the ground state entanglement. The condition is written in terms of the ground state entanglement and the partition function and it gives transition temperatures below which entanglement is guaranteed to survive. It is flexible and can be easily adapted to consider entanglement for different splittings, as well as be weakened to allow easier calculations by approximations. Examples where the condition is calculated are given. These examples allow us to characterize a minimum gapping behavior for the survival of entanglement in the thermodynamic limit. Further, the same technique can be used to find noise thresholds in the generation of useful resource states for one-way quantum computing.

Keywords

Cite

@article{arxiv.quant-ph/0606103,
  title  = {Survival of entanglement in thermal states},
  author = {Damian Markham and Janet Anders and Vlatko Vedral and Mio Murao and Akimasa Miyake},
  journal= {arXiv preprint arXiv:quant-ph/0606103},
  year   = {2008}
}

Comments

6 pages, 2 figures. Changes made in line with publication recommendations. Motivation and concequences of result clarified, with the addition of one more example, which applies the result to give noise thresholds for measurement based quantum computing. New author added with new results