## Decoherence in discrete quantum walks (2003)

Venue: | Selected Lectures from DICE 2002. Lecture Notes in Physics, 633:253–267 |

Citations: | 4 - 0 self |

### BibTeX

@INPROCEEDINGS{Kendon03decoherencein,

author = {Viv Kendon and Ben Tregenna},

title = {Decoherence in discrete quantum walks},

booktitle = {Selected Lectures from DICE 2002. Lecture Notes in Physics, 633:253–267},

year = {2003},

pages = {030118--2}

}

### OpenURL

### Abstract

Abstract. We present an introduction to coined quantum walks on regular graphs, which have been developed in the past few years as an alternative to quantum Fourier transforms for underpinning algorithms for quantum computation. We then describe our results on the effects of decoherence on these quantum walks on a line, cycle and hypercube. We find high sensitivity to decoherence, increasing with the number of steps in the walk, as the particle is becoming more delocalised with each step. However, the effect of a small amount of decoherence can be to enhance the properties of the quantum walk that are desirable for the development of quantum algorithms, such as fast mixing times to uniform distributions. 1 Introduction to Quantum Walks Quantum walks are based on a generalisation of classical random walks, which have found many applications in the field of computing. Examples of the power of classical random walks to solve hard problems include algorithms for solving k-SAT [1], estimating the volume of a convex body [2], and approximation of