Scattering quantum random-walk search with errors

A. Gábris, T. Kiss, and I. Jex
Phys. Rev. A 76, 062315 – Published 20 December 2007

Abstract

We analyze the realization of a quantum-walk search algorithm in a passive, linear optical network. The specific model enables us to consider the effect of realistic sources of noise and losses on the search efficiency. Photon loss uniform in all directions is shown to lead to the rescaling of search time. Deviation from directional uniformity leads to the enhancement of the search efficiency compared to uniform loss with the same average. In certain cases even increasing loss in some of the directions can improve search efficiency. We show that while we approach the classical limit of the general search algorithm by introducing random phase fluctuations, its utility for searching is lost. Using numerical methods, we found that for static phase errors the averaged search efficiency displays a damped oscillatory behavior that asymptotically tends to a nonzero value.

  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
3 More
  • Received 20 January 2007

DOI:https://doi.org/10.1103/PhysRevA.76.062315

©2007 American Physical Society

Authors & Affiliations

A. Gábris1, T. Kiss1, and I. Jex2

  • 1Research Institute for Solid State Physics and Optics, H-1525 Budapest, P.O. Box 49, Hungary
  • 2Department of Physics, FJFI ČVUT, Břehová 7, 115 19 Praha 1-Staré Město, Czech Republic

Article Text (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 76, Iss. 6 — December 2007

Reuse & Permissions
Access Options
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review A

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×