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Related papers: Controlling quantum walks with coin eigenstates

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We consider pretty good state transfer in coined quantum walks between antipodal vertices on the hypercube $Q_d$. When $d$ is a prime, this was proven to occur in the arc-reversal walk with Grover coins. We extend this result by…

Combinatorics · Mathematics 2024-12-31 Hanmeng Zhan

Quantum versions of random walks on the line and the cycle show a quadratic improvement over classical random walks in their spreading rates and mixing times respectively. Non-unitary quantum walks can provide a useful optimisation of these…

Quantum Physics · Physics 2008-03-25 Viv Kendon , Olivier Maloyer

We introduce the Peierls substitution to a two-dimensional discrete-time quantum walk on a square lattice to examine the spreading dynamics and the coin-position entanglement in the presence of an artificial gauge field. We use the ratio of…

Quantum Physics · Physics 2015-10-28 İ. Yalçınkaya , Z. Gedik

Using resonant interaction between atoms and the field in a high quality cavity, we show how to realize quantum random walks as proposed by Aharonov et al [Phys. Rev. A {\bf48}, 1687 (1993)]. The atoms are driven strongly by a classical…

Quantum Physics · Physics 2009-11-11 G S Agarwal , P K Pathak

We propose an implementation of a quantum walk on a circle on an optomechanical system by encoding the walker on the phase space of a radiation field and the coin on a two-level state of a mechanical resonator. The dynamics of the system is…

Quantum Physics · Physics 2015-09-24 Jalil Khatibi Moqadam , Renato Portugal , Marcos Cesar de Oliveira

We investigate a quantum walk on a ring represented by a directed triangle graph with complex edge weights and monitored at a constant rate until the quantum walker is detected. To this end, the first hitting time statistics is recorded…

Quantum Physics · Physics 2024-04-11 Qingyuan Wang , Silin Ren , Ruoyu Yin , Klaus Ziegler , Eli Barkai , Sabine Tornow

We introduce the driven discrete time quantum walk, where walkers are added during the walk instead of only at the beginning. This leads to interference in walker number and very different dynamics when compared to the original quantum…

Quantum Physics · Physics 2016-09-01 Craig S. Hamilton , Sonja Barkhofen , Linda Sansoni , Igor Jex , Christine Silberhorn

Quantum random walks are shown to have non-intuitive dynamics which makes them an attractive area of study for devising quantum algorithms for long-standing open problems as well as those arising in the field of quantum computing. In the…

Quantum Physics · Physics 2009-11-13 K. Manouchehri , J. B. Wang

Open quantum random walks (OQRWs) deal with quantum random motions on the line for systems with internal and orbital degrees of freedom. The internal system behaves as a quantum random gyroscope coding for the direction of the orbital…

Mathematical Physics · Physics 2015-06-15 Michel Bauer , Denis Bernard , Antoine Tilloy

The preparation of initial superposition states of discrete-time quantum walks (DTQWs) are necessary for the study and applications of DTQWs. In linear optics, it is easy to prepare initial superposition states of the coin, which are always…

Existence of the eigenvalues of the discrete-time quantum walks is deeply related to localization of the walks. We revealed the distributions of the eigenvalues given by the splitted generating function method (the SGF method) of the…

Spectral Theory · Mathematics 2020-02-19 Shimpei Endo , Takako Endo , Takashi Komatsu , Norio Konno

Hitting times for discrete quantum walks on graphs give an average time before the walk reaches an ending condition. To be analogous to the hitting time for a classical walk, the quantum hitting time must involve repeated measurements as…

Quantum Physics · Physics 2009-11-11 Hari Krovi , Todd A. Brun

We derive analytical results for continuous-time quantum walks from a new class of initial states with tunable delocalization. The dynamics are governed by a Hamiltonian with complex hopping amplitudes. We provide closed-form equations for…

Quantum Physics · Physics 2026-02-10 Jefferson J. Ximenes , Marcelo A. Pires , José M. Villas-Bôas

A central feature of quantum mechanics is that a measurement is intrinsically probabilistic. As a result, continuously monitoring a quantum system will randomly perturb its natural unitary evolution. The ability to control a quantum system…

Quantum Physics · Physics 2014-09-04 S. J. Weber , A. Chantasri , J. Dressel , A. N. Jordan , K. W. Murch , I. Siddiqi

Quantum random walks (QRWs) are random processes in which the resulting probability density of the "walker" state, whose movement is governed by a "coin" state, is described in a non-classical manner. Previously, Q-plates have been used to…

The three-state Grover walk on a line exhibits the localization effect characterized by a non-vanishing probability of the particle to stay at the origin. We present two continuous deformations of the Grover walk which preserve its…

Quantum Physics · Physics 2012-06-06 Martin Stefanak , Iva Bezdekova , Igor Jex

Exploiting multi-dimensional quantum walks as feasible platforms for quantum computation and quantum simulation is attracting constantly growing attention from a broad experimental physics community. Here, we propose a two-dimensional…

Quantum Physics · Physics 2015-01-22 Carlo Di Franco , Mauro Paternostro

Recently, a new model of quantum walk, utilizing recycled coins, was introduced; however little is yet known about its properties. In this paper, we study its behavior on the cycle graph. In particular, we will consider its time averaged…

Quantum Physics · Physics 2015-05-27 Walter O. Krawec

A quantum random walk on the integers exhibits pseudo memory effects, in that its probability distribution after N steps is determined by reshuffling the first N distributions that arise in a classical random walk with the same initial…

Quantum Physics · Physics 2009-11-10 Anthony J. Bracken , Demosthenes Ellinas , Ioannis Tsohantjis

Quantum state transfer between different sites is a significant problem for quantum networks and quantum computers. By selecting quantum walks with two coins as the basic model and two coin spaces as the communication carriers, we…

Quantum Physics · Physics 2019-12-13 Yun Shang , Meng Li