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Related papers: Invariance in Quantum Walks

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We implement the proof of principle for the quantum walk of one ion in a linear ion trap. With a single-step fidelity exceeding 0.99, we perform three steps of an asymmetric walk on the line. We clearly reveal the differences to its…

Quantum Physics · Physics 2015-05-13 H. Schmitz , R. Matjeschk , Ch. Schneider , J. Glueckert , M. Enderlein , T. Huber , T. Schaetz

Quantum walks exhibit many unique characteristics compared to classical random walks. In the classical setting, self-avoiding random walks have been studied as a variation on the usual classical random walk. Classical self-avoiding random…

Quantum Physics · Physics 2015-01-08 Elizabeth Camilleri , Peter P. Rohde , Jason Twamley

Quantum walk acts obviously different from its classical counterpart, but decoherence will lessen and close the gap between them. To understand this process, it is necessary to investigate the evolution of quantum walk under different…

Quantum Physics · Physics 2015-06-04 Peng Xue , Yongsheng Zhang

We use simple deterministic dynamical systems as coins in studying quantum walks. These dynamical systems can be chosen to display, in the classical limit, a range of behaviors from the integrable to chaotic, or deterministically random. As…

Quantum Physics · Physics 2007-05-23 Arul Lakshminarayan

We present the first robust implementation of a coined quantum walk over five steps using only passive optical elements. By employing a fiber network loop we keep the amount of required resources constant as the walker's position Hilbert…

Quantum Physics · Physics 2015-05-14 A. Schreiber , K. N. Cassemiro , V. Potocek , A. Gabris , P. J. Mosley , E. Andersson , I. Jex , Ch. Silberhorn

Recently, a new model of quantum walk, utilizing recycled coins, was introduced; however little is yet known about its properties. In this paper, we study its behavior on the cycle graph. In particular, we will consider its time averaged…

Quantum Physics · Physics 2015-05-27 Walter O. Krawec

We introduce a variation of the discrete time quantum walk, the nonreversal quantum walk, which does not step back onto a position which it has just occupied. This allows us to simulate a dimer and we achieve it by introducing a new type of…

Quantum Physics · Physics 2014-06-27 T. J. Proctor , K. E. Barr , B. Hanson , S. Martiel , V. Pavlovic , A. Bullivant , V. M. Kendon

We advance the previous studies of quantum walks on the line with two coins. Such four-state quantum walks driven by a three-direction shift operator may have nonzero stationary distributions (localization), thus distinguishing themselves…

Quantum Physics · Physics 2011-07-19 Chaobin Liu

Quantum versions of random walks on the line and the cycle show a quadratic improvement over classical random walks in their spreading rates and mixing times respectively. Non-unitary quantum walks can provide a useful optimisation of these…

Quantum Physics · Physics 2008-03-25 Viv Kendon , Olivier Maloyer

The extremely fascinating behaviors of the quantum walks of particles, which differ much from the classical counterparts, have attracted many physicists. Here we investigate another interesting part of the quantum walks, that is the quantum…

Quantum Physics · Physics 2010-11-23 Tian-Li Feng , Yong-Sheng Zhang , Guang-Ming Zhao , Sheng Liu , Guang-Can Guo

In discrete time, coined quantum walks, the coin degrees of freedom offer the potential for a wider range of controls over the evolution of the walk than are available in the continuous time quantum walk. This paper explores some of the…

Quantum Physics · Physics 2009-11-10 Ben Tregenna , Will Flanagan , Rik Maile , Viv Kendon

It is demonstrated that in gate-based quantum computing architectures quantum walk is a natural mathematical description of quantum gates. It originates from field-matter interaction driving the system, but is not attached to specific qubit…

Quantum Physics · Physics 2020-05-08 Dmitry Solenov

Quantum walk research has mainly focused on evolutions due to repeated applications of time-independent unitary coin operators. However, the idea of controlling the single particle evolution using time-dependent unitary coins has still been…

Quantum Physics · Physics 2019-09-19 Shrabanti Dhar , Abdul Khaleque , Tushar Kanti Bose

We clarify that coined quantum walk is determined by only the choice of local quantum coins. To do so, we characterize coined quantum walks on graph by disjoint Euler circles with respect to symmetric arcs. In this paper, we introduce a new…

Mathematical Physics · Physics 2014-05-08 Yusuke Higuchi , Norio Konno , Iwao Sato , Etsuo Segawa

When confined to a topological environment consisting of a cycle coupled with a half-line, quantum walks exhibit long-term statistical tendencies which differ dramatically from the tendencies of classical random walks in the same…

Quantum Physics · Physics 2015-06-08 Forrest Ingram-Johnson , Chaobin Liu , Nelson Petulante

In this paper we extend the concept of persistence, well defined for classical stochastic dynamics, to the context of quantum dynamics. We demonstrate the idea via quantum random walk and a successive measurement scheme, where persistence…

Statistical Mechanics · Physics 2015-05-18 Sanchari Goswami , Parongama Sen , Arnab Das

For a continuous-time quantum walk on a line the variance of the position observable grows quadratically in time, whereas, for its classical counterpart on the same graph, it exhibits a linear, diffusive, behaviour. A quantum walk, thus,…

Quantum Physics · Physics 2008-01-30 Diego de Falco , Dario Tamascelli

We introduce an analytically treatable spin decoherence model for quantum walk on a line that yields the exact position probability distribution of an unbiased classical random walk at all-time scales. This spin decoherence model depicts a…

Quantum Physics · Physics 2018-09-05 Mahesh N. Jayakody , Asiri Nanayakkara

Quantum walk is one of the main tools for quantum algorithms. Defined by analogy to classical random walk, a quantum walk is a time-homogeneous quantum process on a graph. Both random and quantum walks can be defined either in continuous or…

Quantum Physics · Physics 2010-01-10 Andrew M. Childs

A quantum walker moves on the integers with four extra degrees of freedom, performing a coin-shift operation to alter its internal state and position at discrete units of time. The time evolution is described by a unitary process. We focus…

Quantum Physics · Physics 2018-08-16 Takuya Machida , F. Alberto Grunbaum