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Related papers: Limit theorems for quantum walks with memory

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We focus on a 2-period time-dependent quantum walk on the half line in this paper. The quantum walker launches at the edge of the half line in a localized superposition state and its time evolution is carried out with two unitary operations…

Quantum Physics · Physics 2020-08-28 Takuya Machida

We make and generalize the observation that summing of probability amplitudes of a discrete-time quantum walk over partitions of the walking graph consistent with the step operator results in a unitary evolution on the reduced graph which…

Quantum Physics · Physics 2020-04-06 Václav Potoček

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

Focusing on a continuous-time quantum walk on $\mathbb{Z}=\left\{0,\pm 1,\pm 2,\ldots\right\}$, we analyze a probability distribution with which the quantum walker is observed at a position. The walker launches off at a localized state and…

Quantum Physics · Physics 2023-09-06 Takuya Machida

We perform the scattering analysis of the evolution operator of quantum walks with an anisotropic coin, and we prove a weak limit theorem for their asymptotic velocity. The quantum walks that we consider include one-defect models, two-phase…

Mathematical Physics · Physics 2018-06-13 S. Richard , A. Suzuki , R. Tiedra de Aldecoa

Lazy quantum walks were presented by Andrew M. Childs to prove that the continuous-time quantum walk is a limit of the discrete-time quantum walk [Commun.Math.Phys.294,581-603(2010)]. In this paper, we discuss properties of lazy quantum…

Quantum Physics · Physics 2015-09-01 Dan Li , Michael Mc Gettrick , Wei-Wei Zhang , Ke-Jia Zhang

Recurrence of a random walk is described by the Polya number. For quantum walks, recurrence is understood as the return of the walker to the origin, rather than the full-revival of its quantum state. Localization for two dimensional quantum…

Quantum Physics · Physics 2010-11-10 M. Stefanak , B. Kollar , T. Kiss , I. Jex

We consider asymptotic behaviour of a Hadamard walk on a cycle. For a walk which starts with a state in which all the probability is concentrated on one node, we find the explicit formula for the limiting distribution and discuss its…

Quantum Physics · Physics 2015-06-26 Malgorzata Bednarska , Andrzej Grudka , Pawel Kurzynski , Tomasz Luczak , Antoni Wojcik

Noise-enhanced applications in open quantum walk (QW) have recently seen a surge due to their ability to improve performance. However, verifying the success of open QW is challenging, as mixed-state tomography is a resource-intensive…

Based on studies on four specific networks, we conjecture a general relation between the walk dimensions $d_{w}$ of discrete-time random walks and quantum walks with the (self-inverse) Grover coin. In each case, we find that $d_{w}$ of the…

Statistical Mechanics · Physics 2015-06-03 Stefan Boettcher , Stefan Falkner , Renato Portugal

We study a series of one-dimensional discrete-time quantum-walk models labeled by half integers $j=1/2, 1, 3/2, ...$, introduced by Miyazaki {\it et al.}, each of which the walker's wave function has $2j+1$ components and hopping range at…

Quantum Physics · Physics 2008-02-15 Mitsunori Sato , Naoki Kobayashi , Makoto Katori , Norio Konno

We investigate the properties of a quantum walk which can simulate the behavior of a spin $1/2$ particle in a model with an ordinary spatial dimension, and one extra dimension with warped geometry between two branes. Such a setup…

Quantum Physics · Physics 2022-09-19 Andreu Anglés-Castillo , Armando Pérez

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

Quantum walk (QW), which is considered as the quantum counterpart of the classical random walk (CRW), is actually the quantum extension of CRW from the single-coin interpretation. The sequential unitary evolution engenders correlation…

Quantum Physics · Physics 2020-03-11 Jin-Fu Chen , Yu-Han Ma , Chang-Pu Sun

Quantum walks (QWs) exhibit different properties compared with classical random walks (RWs), most notably by linear spreading and localization. In the meantime, random walks that replicate quantum walks, which we refer to as…

Mathematical Physics · Physics 2022-11-01 Tomoki Yamagami , Etsuo Segawa , Nicolas Chauvet , André Röhm , Ryoichi Horisaki , Makoto Naruse

We consider a two-state quantum walk on a line where after the first step an absorbing sink is placed at the origin. The probability of finding the walker at position $j$, conditioned on that it has not returned to the origin, is…

Quantum Physics · Physics 2018-08-08 Mohamed Sabri , Etsuo Segawa , Martin Stefanak

We study large time behavior of quantum walks (QW) with self-dependent coin. In particular, we show scattering and derive the reproducing formula for inverse scattering in the weak nonlinear regime. The proof is based on space-time estimate…

Mathematical Physics · Physics 2017-11-08 Masaya Maeda , Hironobu Sasaki , Etsuo Segawa , Akito Suzuki , Kanako Suzuki

The aim of this paper is to deepen the analysis of the asymptotic behavior of the so-called minimal random walk (MRW) using a new martingale approach. The MRW is a discrete-time random walk with infinite memory that has three regimes…

Probability · Mathematics 2023-06-21 Bernard Bercu , Víctor Hugo Vázquez Guevara

We study the discrete-time quantum walk in one-dimension governed by the Fibonacci transformation .We show localization does not occur for the Fibonacci quantum walk by investigating the stationary distribution of the walk, in addition, we…

Mathematical Physics · Physics 2011-08-29 Clement Ampadu

Quantum walks contribute significantly to developing quantum algorithms and quantum simulations. Here, we introduce a first of its kind one-dimensional quantum walk in the $d$-dimensional quantum domain, where $d>2$, and show its…

Quantum Physics · Physics 2024-10-04 Amit Saha , Debasri Saha , Amlan Chakrabarti