English
Related papers

Related papers: Faster transport with a directed quantum walk

200 papers

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

The formalism of continuous-time quantum walks on graphs has been widely used in the study of quantum transport of energy and information, as well as in the development of quantum algorithms. In experimental settings, however, there is…

Quantum Physics · Physics 2021-05-05 Leonardo Novo , Sofia Ribeiro

Quantum walks are referred to as quantum analogs to random walks in mathematics. They have been studied as quantum algorithms in quantum information for quantum computers. There are two types of quantum walks. One is the discrete-time…

Quantum Physics · Physics 2024-06-26 Takuya Machida

Quantum mechanics still provides new unexpected effects when considering the transport of energy and information. Models of continuous time quantum walks, which implicitly use time-reversal symmetric Hamiltonians, have been intensely used…

Quantum Physics · Physics 2013-08-23 Zoltan Zimboras , Mauro Faccin , Zoltan Kadar , James Whitfield , Ben Lanyon , Jacob Biamonte

Quantum walk is one of the main tools for quantum algorithms. Defined by analogy to classical random walk, a quantum walk is a time-homogeneous quantum process on a graph. Both random and quantum walks can be defined either in continuous or…

Quantum Physics · Physics 2010-01-10 Andrew M. Childs

Discrete time (coined) quantum walks are produced by the repeated application of a constant unitary transformation to a quantum system. By recasting these walks into the setting of periodic perturbations to an otherwise freely evolving…

Quantum Physics · Physics 2007-05-23 O. Buerschaper , K. Burnett

It is demonstrated that in gate-based quantum computing architectures quantum walk is a natural mathematical description of quantum gates. It originates from field-matter interaction driving the system, but is not attached to specific qubit…

Quantum Physics · Physics 2020-05-08 Dmitry Solenov

A continuous-time quantum walk on a dynamic graph evolves by Schr\"odinger's equation with a sequence of Hamiltonians encoding the edges of the graph. This process is universal for quantum computing, but in general, the dynamic graph that…

Quantum Physics · Physics 2022-01-20 Rebekah Herrman , Thomas G. Wong

We show how to construct discrete-time quantum walks on directed, Eulerian graphs. These graphs have tails on which the particle making the walk propagates freely, and this makes it possible to analyze the walks in terms of scattering…

Quantum Physics · Physics 2009-11-13 Edgar Feldman , Mark Hillery

The finite dihedral group generated by one rotation and one flip is the simplest case of the non-abelian group. Cayley graphs are diagrammatic counterparts of groups. In this paper, much attention is given to the Cayley graph of the…

Quantum Physics · Physics 2018-10-02 Wenjing Dai , Jiabin Yuan , Dan Li

Quantum walks have by now been realized in a large variety of different physical settings. In some of these, particularly with trapped ions, the walk is implemented in phase space, where the corresponding position states are not orthogonal.…

Quantum Physics · Physics 2014-04-02 R. Matjeschk , A. Ahlbrecht , M. Enderlein , Ch. Cedzich , A. H. Werner , M. Keyl , T. Schaetz , R. F. Werner

In this study we show a way of achieving the reverse evolution of n-dimensional quantum walks by introducing interventions on the coin degree of freedom during the forward progression of the coin-walker system. Only a single intervention is…

Quantum Physics · Physics 2018-03-23 Mahesh N. Jayakody , Asiri Nanayakkara

A discrete-time Quantum Walk (QW) is essentially an operator driving the evolution of a single particle on the lattice, through local unitaries. Some QWs admit a continuum limit, leading to familiar PDEs (e.g. the Dirac equation). Recently…

Quantum Physics · Physics 2016-09-21 Pablo Arrighi , Stefano Facchini

In the present paper, the first in a series of two, we propose a model of universal quantum computation using a fermionic/bosonic multi-particle continuous-time quantum walk with two internal states (e.g., the spin-up and down states of an…

Quantum Physics · Physics 2023-02-28 Ryo Asaka , Kazumitsu Sakai , Ryoko Yahagi

Up to now, relatively few exponential quantum speed-ups have been achieved. Out of them, the welded tree problem (Childs, Cleve, Deotto, Farhi, Gutmann, and Spielman'2003) is one of the unusual examples, as the exponential speed-up is…

Quantum Physics · Physics 2024-05-01 Aleksandrs Belovs

Quantum walks are a promising framework for developing quantum algorithms and quantum simulations. They represent an important test case for the application of quantum computers. Here we present different forms of discrete-time quantum…

We explore a discrete-time, coined quantum walk on a quantum network where the coherent superposition of walker-moves originates from the unitary interaction of the walker-coin with the qubit degrees of freedom in the quantum network. The…

Quantum Physics · Physics 2024-06-04 Jigyen Bhavsar , Shashank Shekhar , Siddhartha Santra

The "quantum walk" has emerged recently as a paradigmatic process for the dynamic simulation of complex quantum systems, entanglement production and quantum computation. Hitherto, photonic implementations of quantum walks have mainly been…

We propose a scheme to implement the one-dimensional coined quantum walk with electrons transported through a two-dimensional network of spintronic semiconductor quantum rings. The coin degree of freedom is represented by the spin of the…

Mesoscale and Nanoscale Physics · Physics 2009-07-30 Orsolya Kálmán , Tamás Kiss , Péter Földi

A discrete time quantum walker is considered in one dimension, where at each step, the translation can be more than one unit length chosen randomly. In the simplest case, the probability that the distance travelled is $\ell$ is taken as…

Quantum Physics · Physics 2018-10-17 Parongama Sen