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Related papers: Hitting Time of Quantum Walks with Perturbation

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Quantum walk serves as a versatile tool for universal quantum computing and algorithmic research. However, the implementation of discrete-time quantum walks (DTQWs) with superconducting circuits is still constrained by some limitations such…

For random walks on graph $\mathcal{G}$ with $n$ vertices and $m$ edges, the mean hitting time $H_j$ from a vertex chosen from the stationary distribution to vertex $j$ measures the importance for $j$, while the Kemeny constant…

Social and Information Networks · Computer Science 2024-12-17 Haisong Xia , Wanyue Xu , Zuobai Zhang , Zhongzhi Zhang

We present analytical treatment of quantum walks on a cycle graph. The investigation is based on a realistic physical model of the graph in which decoherence is induced by continuous monitoring of each graph vertex with nearby quantum point…

Quantum Physics · Physics 2007-05-23 Dmitry Solenov , Leonid Fedichkin

A new model of quantum random walks is introduced, on lattices as well as on finite graphs. These quantum random walks take into account the behavior of open quantum systems. They are the exact quantum analogues of classical Markov chains.…

Quantum Physics · Physics 2014-02-14 S. Attal , F. Petruccione , C. Sabot , I. Sinayskiy

We study the effect of small decoherence in continuous-time quantum walks on long-range interacting cycles, which are constructed by connecting all the two nodes of distance m on the cycle graph. In our investigation, each node is…

Quantum Physics · Physics 2015-05-13 S. Salimi , R. Radgohar

In this paper, a study on discrete-time coined quantum walks on the line is presented. Clear mathematical foundations are still lacking for this quantum walk model. As a step towards this objective, the following question is being…

Quantum Physics · Physics 2013-01-01 Marcos Villagra , Masaki Nakanishi , Shigeru Yamashita , Yasuhiko Nakashima

In the present paper, we investigate the relationship between hitting times and hitting probabilities in discrete-time imprecise Markov chains (IMCs). We define lower and upper hitting times and probabilities for IMCs whose set of…

Probability · Mathematics 2026-03-18 Marco Sangalli , Erik Quaeghebeur , Thomas Krak

We study the absorption time and spreading rate of the discrete-time quantum walk propagating on a line in the presence or absence of an absorber. We analytically establish that in the presence of an absorber, the average absorption time of…

Quantum Physics · Physics 2026-02-17 Shuva Mondal , Amrita Mandal , Ujjwal Sen

We prove analytical results showing that decoherence can be useful for mixing time in a continuous-time quantum walk on finite cycles. This complements the numerical observations by Kendon and Tregenna (Physical Review A 67 (2003), 042315)…

Quantum Physics · Physics 2007-05-23 Leonid Fedichkin , Dmitry Solenov , Christino Tamon

Given a discrete source distribution $\mu$ and discrete target distribution $\nu$ on a common finite state space $\mathcal{X}$, we are tasked with transporting $\mu$ to $\nu$ using a given discrete-time Markov chain $X$ with the quickest…

Probability · Mathematics 2018-07-23 Michael C. H. Choi

In a Markov chain started at a state $x$, the hitting time $\tau(y)$ is the first time that the chain reaches another state $y$. We study the probability $\mathbf{P}_x(\tau(y) = t)$ that the first visit to $y$ occurs precisely at a given…

Probability · Mathematics 2014-08-06 James Norris , Yuval Peres , Alex Zhai

We study the first detected recurrence time problem of continuous-time quantum walks on graphs. While previous works have employed projective measurements to determine the first return time, we implement a protocol based on weak…

Quantum Physics · Physics 2025-06-27 Tim Heine , Eli Barkai , Klaus Ziegler , Sabine Tornow

Quantum random walks have been much studied recently, largely due to their highly nonclassical behavior. In this paper, we study one possible route to classical behavior for the discrete quantum random walk on the line: the use of multiple…

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

For a discrete time quantum walk (QW) on the $N$-cycle, allowing for decoherence on the coin, we derive a number of new results, including an explicit formula for the position probability distribution. For a QW of this type, we show that…

Quantum Physics · Physics 2015-05-13 Chaobin Liu , Nelson Petulante

We investigate the splitting probability of a monitored continuous-time quantum walk with two targets and show that, in stark contrast to a classical random walk, it exhibits a nonanalytic, phase-transition-like behavior controlled by the…

Statistical Mechanics · Physics 2026-01-23 Prashant Singh , David A. Kessler , Eli Barkai

We study hitting times in simple random walks on graphs, which measure the time required to reach specific target vertices. Our main result establishes a sharp lower bound for the variance of hitting times. For a simple random walk on a…

Probability · Mathematics 2024-03-25 Rafael Chiclana , Yuval Peres

Szegedy's quantization of a reversible Markov chain provides a quantum walk whose spectral gap is quadratically larger than that of the classical walk. Quantum computers are therefore expected to provide a speedup of Metropolis-Hastings…

Quantum Physics · Physics 2026-05-28 Baptiste Claudon , Pablo Rodenas-Ruiz , Jean-Philip Piquemal , Pierre Monmarché

The time it takes a random walker in a lattice to reach the origin from another vertex $x$, has infinite mean. If the walker can restart the walk at $x$ at will, then the minimum expected hitting time $T(x,0)$ (minimized over restarting…

Probability · Mathematics 2010-05-25 Svante Janson , Yuval Peres

In discrete-time quantum walk (DTQW) the walker's coin space entangles with the position space after the very first step of the evolution. This phenomenon may be exploited to obtain the value of the coin parameter $\theta$ by performing…

Quantum Physics · Physics 2019-07-10 Shivani Singh , C. M. Chandrashekar , Matteo G. A. Paris

We present a detailed analysis of continuous time quantum walks (CTQW) with both position and transition defects defined at a single point in the line. Analytical solutions of both traveling waves or bound states are obtained, which provide…

Quantum Physics · Physics 2015-09-08 Zhi-Jian Li , J. B. Wang