BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Talks.cam//talks.cam.ac.uk//
X-WR-CALNAME:Talks.cam
BEGIN:VEVENT
SUMMARY:Efficient decoders for qudit topological codes - Browne\, D (Unive
 rsity College London)
DTSTART:20131121T140000Z
DTEND:20131121T150000Z
UID:TALK48945@talks.cam.ac.uk
CONTACT:Mustapha Amrani
DESCRIPTION:For a quantum error correcting code\, a decoder is a (classica
 l) algorithm\, which given the set of measurement outcomes of the stabilis
 er generators of the code (the syndrome) outputs a set of unitarites which
  may be applied to correct the error. Since the mapping between errors and
  syndromes is not one-to-one\, decoders attempt to output an operator whic
 h is most likely to correct the error\, given the underlying error model.\
 n\nFor the qubit toric code\, the most widely used decoder is the Minimum 
 Weight Perfect Matching algorithm. This decoder utilises some very special
  properties of the qubit toric code\, it  is not applicable\, in general\,
  to other topological codes. In [1] we introduce two decoders for the qudi
 t (d>2) toric code. One of them is a generalisation of the decoder introdu
 ced by Bravyi and Haah [2] for the cubic code\, and the other is a general
 isation of an RG-based algorithm proposed by Duclos-Cianci and Poulin [3].
  I will focus on the former in my talk\, introducing the decoder\, its lim
 itations\, and how those limitations can be overcome to produce an efficie
 nt and effective decoder for high d qudit toric codes. I will finish my ta
 lk by comparing the thresholds achieved with these different decoder strat
 egies with a conjectured optimal threshold for these codes.\n\n[1] H. Anwa
 r\, B. Browne\, E. T. Campbell\, D.E. Browne\, Efficient Decoders for Qudi
 t Topological Codes\, (to appear on the arxiv shortly).\n[2] Sergey Bravyi
 \, Jeongwan Haah\, Analytic and numerical demonstration of quantum self-co
 rrection in the 3D Cubic Code\, arXiv:1112.3252\n[3] Guillaume Duclos-Cian
 ci\, David Poulin\, Fast Decoders for Topological Quantum Codes\, Phys. Re
 v. Lett. 104 050504 (2010)\n
LOCATION:Seminar Room 1\, Newton Institute
END:VEVENT
END:VCALENDAR