One-dimensional quantum walks subject to next-nearest-neighbour hopping decoherence

It is believed that the decoherence will lead to a crossover from quantum to classical for the diffusive behaviour of discrete quantum walk in the long time limit. However, a few systems with sub-ballistic diffusive behaviours have been found in some non-unitary quantum walks. In this paper, we stud...

Full description

Saved in:
Bibliographic Details
Published inQuantum information processing Vol. 14; no. 7; pp. 2357 - 2372
Main Authors Zhao, Jing, Tong, Peiqing
Format Journal Article
LanguageEnglish
Published New York Springer US 01.07.2015
Subjects
Data Structures and Information Theory
Mathematical Physics
Physics
Physics and Astronomy
Quantum Computing
Quantum Information Technology
Quantum Physics
Spintronics
Quantum algorithms
Decoherence
Sub-ballistic diffusion
Quantum walk
Online AccessGet full text

Cover

More Information
Summary:It is believed that the decoherence will lead to a crossover from quantum to classical for the diffusive behaviour of discrete quantum walk in the long time limit. However, a few systems with sub-ballistic diffusive behaviours have been found in some non-unitary quantum walks. In this paper, we study the one-dimensional discrete quantum walks subject to a short-range hopping decoherence, i.e. with a probability the walker could hop to next-nearest-neighbour lattices unilaterally and/or bilaterally in one time step. We find that, when the decoherence effects only come from the bilateral hopping operation, the diffusive behaviours of quantum walks are sub-ballistic and the distributions of position exhibit three peaks. These results are quite different from those of the previous non-unitary quantum walks. Our results could be used to improve the algorithmic properties of quantum walk due to its faster diffusive speed and more uniform spreading.
ISSN:1570-0755
1573-1332
DOI:10.1007/s11128-015-1012-2