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Related papers: Non-Unitary Quantum Walks on Hyper-Cycles

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Mixing properties of discrete-time quantum walks on two-dimensional grids with torus-like boundary conditions are analyzed, focusing on their connection to the complexity of the corresponding abstract search algorithm. In particular, an…

Quantum Physics · Physics 2012-05-18 F. L. Marquezino , R. Portugal , G. Abal

Due to the unitary evolution, quantum walks display different dynamical features from that of classical random walks. In contrast to this expectation, in this work, we show that extreme events can arise in unitary dynamics and its…

Quantum Physics · Physics 2025-02-27 Nisarg Vyas , M. S. Santhanam

Quantum versions of random walks on the line and cycle show a quadratic improvement in their spreading rate and mixing times respectively. The addition of decoherence to the quantum walk produces a more uniform distribution on the line, and…

Quantum Physics · Physics 2007-07-26 Olivier Maloyer , Viv Kendon

Coherent evolution governs the behaviour of all quantum systems, but in nature it is often subjected to influence of a classical environment. For analysing quantum transport phenomena quantum walks emerge as suitable model systems. In…

Consider a discrete-time quantum walk on the $N$-cycle subject to decoherence both on the coin and the position degrees of freedom. By examining the evolution of the density matrix of the system, we derive some new conclusions about the…

Quantum Physics · Physics 2011-07-20 Chaobin Liu , Nelson Petulante

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 effect of decoherence on the continuous-time quantum walk on the hypercube is revisited. Previously, an exact solution was found for a decoherence model that preserved the effective tensor-product form of the dynamics. Here a new model…

Quantum Physics · Physics 2009-11-13 Frederick W. Strauch

Quantum walks on graphs have shown prioritized benefits and applications in wide areas. In some scenarios, however, it may be more natural and accurate to mandate high-order relationships for hypergraphs, due to the density of information…

Quantum Physics · Physics 2017-09-26 Ying Liu , Jiabin Yuan , Bojia Duan , Dan Li

Classical random walks on well-behaved graphs are rapidly mixing towards the uniform distribution. Moore and Russell showed that a continuous quantum walk on the hypercube is instantaneously uniform mixing. We show that the continuous-time…

Quantum Physics · Physics 2007-05-23 Amir Ahmadi , Ryan Belk , Christino Tamon , Carolyn Wendler

We present a theoretical framework for the analysis of amplitude transfer in Quantum Variational Algorithms (QVAs) for combinatorial optimisation with mixing unitaries defined by vertex-transitive graphs, based on their continuous-time…

Quantum Physics · Physics 2024-06-24 Edric Matwiejew , Jingbo B. Wang

Quantum walks are expected to provide useful algorithmic tools for quantum computation. This paper introduces absorbing probability and time of quantum walks and gives both numerical simulation results and theoretical analyses on Hadamard…

Quantum Physics · Physics 2009-11-07 Tomohiro Yamasaki , Hirotada Kobayashi , Hiroshi Imai

We propose a general framework for quantum walks on d-dimensional spaces. We investigate asymptotic behavior of these walks. Among them, existence of limit distribution of homogeneous walks is proved. In this theorem, the support of the…

Mathematical Physics · Physics 2021-05-19 Hiroki Sako

We introduce a continuous-time quantum walk on an ultrametric space corresponding to the set of p-adic integers and compute its time-averaged probability distribution. It is shown that localization occurs for any location of the ultrametric…

Quantum Physics · Physics 2009-03-24 Norio Konno

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

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…

We study quantum transport on finite discrete structures and we model the process by means of continuous-time quantum walks. A direct and effective comparison between quantum and classical walks can be attained based on the average…

Quantum Physics · Physics 2008-10-08 E. Agliari , A. Blumen , O. Muelken

Quantum random walks represent a powerful tool for the implementation of various quantum algorithms. We consider a convolution problem for the graphs which provide quantum and classical random walks. We suggest a new method for lattices and…

Quantum Physics · Physics 2025-07-23 Roman Abramov , Leonid Fedichkin , Dmitry Tsarev , Alexander Alodjants

The quantum random walk has been much studied recently, largely due to its highly nonclassical behavior. In this paper, we study one possible route to classical behavior for the discrete quantum walk on the line: the presence of decoherence…

Quantum Physics · Physics 2009-11-07 Todd A. Brun , Hilary A. Carteret , Andris Ambainis

We study the transition matrix of a quantum walk on strongly regular graphs. It is proposed by Emms, Hancock, Severini and Wilson in 2006, that the spectrum of $S^+(U^3)$, a matrix based on the amplitudes of walks in the quantum walk,…

Combinatorics · Mathematics 2015-11-09 Chris Godsil , Krystal Guo , Tor G. J. Myklebust

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