English
Related papers

Related papers: A localized quantum walk with a gap in distributio…

200 papers

We study how a single lattice defect in a discrete time quantum walk affects the return probability of a quantum particle. This defect at the starting position is modeled by a quantum coin that is distinct from the others over the lattice.…

Quantum Physics · Physics 2021-06-29 Laurita I. da S. Teles , Edgard P. M. Amorim

It has been discovered that open quantum walks diffusively distribute in space, since they were introduced in 2012. Indeed, some limit distributions have been demonstrated and most of them are described by Gaussian distributions. We operate…

Quantum Physics · Physics 2021-12-20 Takuya Machida

We introduce and study a class of discrete-time quantum walks on a one-dimensional lattice. In contrast to the standard homogeneous quantum walks, coin operators are inhomogeneous and depend on their positions in this class of models. The…

Quantum Physics · Physics 2010-09-17 Yutaka Shikano , Hosho Katsura

We investigate quantum walks in multiple dimensions with different quantum coins. We augment the model by assuming that at each step the amplitudes of the coin state are multiplied by random phases. This model enables us to study in detail…

Quantum Physics · Physics 2009-11-13 Jozef Kosik , Vladimir Buzek , Mark Hillery

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

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 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

We study numerically the behavior of continuous-time quantum walks over networks which are topologically equivalent to square lattices. On short time scales, when placing the initial excitation at a corner of the network, we observe a fast,…

Quantum Physics · Physics 2009-11-11 Oliver Muelken , Antonio Volta , Alexander Blumen

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

We examine an unexplored quantum phenomenon we call oscillatory localization, where a discrete-time quantum walk with Grover's diffusion coin jumps back and forth between two vertices. We then connect it to the power dissipation of a…

Quantum Physics · Physics 2016-12-21 Andris Ambainis , Krišjānis Prūsis , Jevgēnijs Vihrovs , Thomas G. Wong

A return probability of random walks is one of the interesting subjects. As it is well known, the return probability strongly depends on the structure of the space where the random waker moves. On the other hand, the return probability of…

Quantum Physics · Physics 2016-02-17 Takuya Machida

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

In this paper, we study discrete-time quantum walks on one-dimensional lattices. We find that the coherent dynamics depends on the initial states and coin parameters. For infinite size of lattice, we derive an explicit expression for the…

Cellular Automata and Lattice Gases · Physics 2015-05-18 Xin-Ping Xu

We investigate the use of discrete-time quantum walks to sample from an almost-uniform distribution, in the absence of any external source of randomness. Integers are encoded on the vertices of a cycle graph, and a quantum walker evolves…

Quantum Physics · Physics 2025-11-12 Marco Radaelli , Claudia Benedetti , Stefano Olivares

We study transport within a spatially heterogeneous one-dimensional quantum walk with a combination of hierarchical and random barriers. Recent renormalization group calculations for a spatially disordered quantum walk with a regular…

Quantum Physics · Physics 2022-06-09 Richa Sharma , Stefan Boettcher

Coined quantum walks may be interpreted as the motion in position space of a quantum particle with a spin degree of freedom; the dynamics are determined by iterating a unitary transformation which is the product of a spin transformation and…

Quantum Physics · Physics 2007-05-23 Alex D. Gottlieb , Svante Janson , Petra F. Scudo

We revisit the one dimensional discrete time quantum walk with 3 states and the Grover coin. We derive analytic expressions for observed the localization, an long time approximation for the probability density function (PDF). We also…

Quantum Physics · Physics 2014-10-29 Stefan Falkner , Stefan Boettcher

We consider a discrete-time quantum walk $W_{t,\kappa}$ at time $t$ on a graph with joined half lines $\mathbb{J}_\kappa$, which is composed of $\kappa$ half lines with the same origin. Our analysis is based on a reduction of the walk on a…

Quantum Physics · Physics 2012-01-12 Kota Chisaki , Norio Konno , Etsuo Segawa

Quantum walks are versatile simulators of topological phases and phase transitions as observed in condensed matter physics. Here, we utilize a step dependent coin in quantum walks and investigate what topological phases we can simulate with…

Quantum Physics · Physics 2019-12-16 S. Panahiyan , S. Fritzsche

This letter treats the quantum random walk on the line determined by a 2 times 2 unitary matrix U. A combinatorial expression for the mth moment of the quantum random walk is presented by using 4 matrices, P, Q, R and S given by U. The…

Quantum Physics · Physics 2007-05-23 Norio Konno
‹ Prev 1 3 4 5 6 7 10 Next ›