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Related papers: From open quantum walks to unitary quantum walks

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In the present paper, we construct QMC (Quantum Markov Chains) associated with Open Quantum Random Walks such that the transition operator of the chain is defined by OQRW and the restriction of QMC to the commutative subalgebra coincides…

Mathematical Physics · Physics 2022-09-14 Farrukh Mukhamedov , Abdessatar Souissi , Tarek Hamdi

Motivated by the immense success of random walk and Markov chain methods in the design of classical algorithms, we consider_quantum_ walks on graphs. We analyse in detail the behaviour of unbiased quantum walk on the line, with the example…

Quantum Physics · Physics 2007-05-23 Ashwin Nayak , Ashvin Vishwanath

We study the asymptotic position distribution of general quantum walks on a lattice, including walks with a random coin, which is chosen from step to step by a general Markov chain. In the unitary (i.e., non-random) case, we allow any…

Quantum Physics · Physics 2011-04-21 Andre Ahlbrecht , Holger Vogts , Albert H. Werner , Reinhard F. Werner

A random walk is known as a random process which describes a path including a succession of random steps in the mathematical space. It has increasingly been popular in various disciplines such as mathematics and computer science.…

Social and Information Networks · Computer Science 2020-08-11 Feng Xia , Jiaying Liu , Hansong Nie , Yonghao Fu , Liangtian Wan , Xiangjie Kong

Discrete-time quantum walk in one-dimension is studied from a path-integral perspective. This enables derivation of a closed-form expression for amplitudes corresponding to any coin-position basis of the state vector of the quantum walker…

Quantum Physics · Physics 2018-03-02 Karthik S. Joshi , S. K. Srivatsa , R. Srikanth

Quantum walks have emerged as an interesting alternative to the usual circuit model for quantum computing. While still universal for quantum computing, the quantum walk model has very different physical requirements, which lends itself more…

Quantum Physics · Physics 2015-05-19 Peter P. Rohde , Andreas Schreiber , Martin Stefanak , Igor Jex , Christine Silberhorn

This paper is concerned with the continuous-time quantum walk on Z, Z^d, and infinite homogeneous trees. By using the generating function method, we compute the limit of the average probability distribution for the general isotropic walk on…

Probability · Mathematics 2015-05-14 Vladislav Kargin

This paper presents a simple model that mimics quantum mechanics (QM) results in terms of probability fields of free particles subject to self-interference, without using Schr\"{o}dinger equation or wavefunctions. Unlike the standard QM…

Quantum Physics · Physics 2015-01-27 Antonio Sciarretta

Quantum walks are a promising framework that can be used to both understand and implement quantum information processing tasks. The quantum stochastic walk is a recently developed framework that combines the concept of a quantum walk with…

Quantum Physics · Physics 2018-12-07 Bruno G. Taketani , Luke C. G. Govia , Frank K. Wilhelm

A proof that continuous time quantum walks are universal for quantum computation, using unweighted graphs of low degree, has recently been presented by Childs [PRL 102 180501 (2009)]. We present a version based instead on the discrete time…

Quantum Physics · Physics 2010-05-06 Neil B. Lovett , Sally Cooper , Matthew Everitt , Matthew Trevers , Viv Kendon

In this note, we discuss a general definition of quantum random walks on graphs and illustrate with a simple graph the possibility of very different behavior between a classical random walk and its quantum analogue. In this graph,…

Quantum Physics · Physics 2007-05-23 Andrew M. Childs , Edward Farhi , Sam Gutmann

Quantum random walks have received much interest due to their non-intuitive dynamics, which may hold the key to a new generation of quantum algorithms. What remains a major challenge is a physical realization that is experimentally viable…

Quantum Physics · Physics 2009-12-18 K Manouchehri , J. B. Wang

Quantum walks are standard tools for searching graphs for marked vertices, and they often yield quadratic speedups over a classical random walk's hitting time. In some exceptional cases, however, the system only evolves by sign flips,…

Quantum Physics · Physics 2017-05-05 Thomas G. Wong , Raqueline A. M. Santos

The study of quantum walks has been shown to have a wide range of applications in areas such as artificial intelligence, the study of biological processes, and quantum transport. The quantum stochastic walk, which allows for incoherent…

Quantum Physics · Physics 2020-02-20 Luke C. G. Govia , Bruno G. Taketani , Peter K. Schuhmacher , Frank K. Wilhelm

Multi-dimensional quantum walks can exhibit highly non-trivial topological structure, providing a powerful tool for simulating quantum information and transport systems. We present a flexible implementation of a 2D optical quantum walk on a…

A major advantage in using Szegedy's formalism over discrete-time and continuous-time quantum walks lies in its ability to define a unitary quantum walk on directed and weighted graphs. In this paper, we present a general scheme to…

Quantum Physics · Physics 2017-06-07 T. Loke , J. B. Wang

We consider the limit distributions of open quantum random walks on one-dimensional lattice space. We introduce a dual process to the original quantum walk process, which is quite similar to the relation of Schr\"odinger-Heisenberg…

Mathematical Physics · Physics 2015-06-11 Norio Konno , Hyun Jae Yoo

We introduce quantum walks with a time-dependent coin, and show how they include, as a particular case, the generalized quantum walk recently studied by Wojcik et al. {[}Phys. Rev. Lett. \textbf{93}, 180601(2004){]} which exhibits…

Quantum Physics · Physics 2009-11-11 M. C. Banuls , C. Navarrete , A. Perez , Eugenio Roldan , J. C. Soriano

In this paper we focus our attention on a particle that follows a unidirectional quantum walk, an alternative version of the nowadays widespread discrete-time quantum walk on a line. Here the walker at each time step can either remain in…

Quantum Physics · Physics 2013-08-01 Miquel Montero

The quantum walk was originally proposed as a quantum mechanical analogue of the classical random walk, and has since become a powerful tool in quantum information science. In this paper, we show that discrete time quantum walks provide a…

Mesoscale and Nanoscale Physics · Physics 2010-09-30 Takuya Kitagawa , Mark S. Rudner , Erez Berg , Eugene Demler