English

Coherent feedback that beats all measurement-based feedback protocols

Quantum Physics 2014-07-31 v2

Abstract

We show that when the speed of control is bounded, there is a widely applicable minimal-time control problem for which a coherent feedback protocol is optimal, and is faster than all measurement-based feedback protocols, where the latter are defined in a strict sense. The superiority of the coherent protocol is due to the fact that it can exploit a geodesic path in Hilbert space, a path that measurement-based protocols cannot follow.

Cite

@article{arxiv.1211.1724,
  title  = {Coherent feedback that beats all measurement-based feedback protocols},
  author = {Kurt Jacobs and Xiaoting Wang and Howard M. Wiseman},
  journal= {arXiv preprint arXiv:1211.1724},
  year   = {2014}
}

Comments

4 pages, revtex4-1, 1 png figure; v2: new (now optimal) coherent protocol, new author

R2 v1 2026-06-21T22:34:41.373Z