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We study a transport phenomenon in certain coined quantum walks where a subspace of states localized at a vertex gets transferred to another vertex. We first develop characterizations for perfect and pretty good subspace state transfer…

Combinatorics · Mathematics 2025-12-01 Yichi Xu , Hanmeng Zhan

We introduce some new perfect state transfer and teleportation schemes by quantum walks with two coins. Encoding the transferred information in coin 1 state and alternatively using two coin operators, we can perfectly recover the…

Quantum Physics · Physics 2018-02-09 Yun Shang , Yu Wang , Meng Li , Ruqian Lu

We show that certain types of quantum walks can be modeled as waves that propagate in a medium with phase and group velocities that are explicitly calculable. Since the group and phase velocities indicate how fast wave packets can propagate…

Quantum Physics · Physics 2013-05-29 Achim Kempf , Renato Portugal

We compare discrete-time quantum walks on graphs to their natural classical equivalents, which we argue are lifted Markov chains, that is, classical Markov chains with added memory. We show that these can simulate quantum walks, allowing us…

Quantum Physics · Physics 2018-09-26 Simon Apers , Alain Sarlette , Francesco Ticozzi

It is shown that discrete-time quantum walks can be used to digitize, i.e., to time discretize fermionic models of continuous-time lattice gauge theory. The resulting discrete-time dynamics is thus not only manifestly unitary, but also…

Quantum Physics · Physics 2025-02-28 Pablo Arnault , Armando Pérez , Pablo Arrighi , Terry Farrelly

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 generalize the discrete quantum walk on the line using a time dependent unitary coin operator. We find an analytical relation between the long-time behaviors of the standard deviation and the coin operator. Selecting the coin time…

Quantum Physics · Physics 2015-05-13 Alejandro Romanelli

Quantum walk (QW) is the quantum analog of the random walk. QW is an integral part of the development of numerous quantum algorithms. Hence, an in-depth understanding of QW helps us to grasp the quantum algorithms. We revisit the…

Quantum Physics · Physics 2021-02-16 Mahesh N. Jayakody , Chandrakala Meena , Priodyuti Pradhan

How self-loops on vertices affect quantum walks is an interesting issue, and self-loops play important roles in quantum walk based algorithms. However, the original model that adjusting the effect of self-loops by changing their number has…

Quantum Physics · Physics 2017-07-04 Huiquan Wang , Jie Zhou , Junjie Wu , Xun Yi

In this work we introduce the concept of a quantum walk on a hypergraph. We show that the staggered quantum walk model is a special case of a quantum walk on a hypergraph.

Quantum Physics · Physics 2020-11-10 Przemysław Sadowski , Łukasz Pawela , Paulina Lewandowska , Ryszard Kukulski

The lackadaisical quantum walk is a discrete-time, coined quantum walk on a graph with a weighted self-loop at each vertex. It uses a generalized Grover coin and the flip-flop shift, which makes it equivalent to Szegedy's quantum Markov…

Quantum Physics · Physics 2020-09-18 Mason L. Rhodes , Thomas G. Wong

The physics of quantum walks on graphs is formulated in Hamiltonian language, both for simple quantum walks and for composite walks, where extra discrete degrees of freedom live at each node of the graph. It is shown how to map between…

Quantum Physics · Physics 2009-11-13 Andrew P. Hines , P. C. E. Stamp

The position density of a "particle" performing a continuous-time quantum walk on the integer lattice, viewed on length scales inversely proportional to the time t, converges (as t tends to infinity) to a probability distribution that…

Quantum Physics · Physics 2013-05-29 Alex D. Gottlieb

We present an introduction to coined quantum walks on regular graphs, which have been developed in the past few years as an alternative to quantum Fourier transforms for underpinning algorithms for quantum computation. We then describe our…

Quantum Physics · Physics 2018-03-28 Viv Kendon , Ben Tregenna

We study one-dimensional quantum walk with four internal degrees of freedom resulted from two entangled qubits. We will demonstrate that the entanglement between the qubits and its corresponding coin operator enable one to steer the…

Quantum Physics · Physics 2020-07-01 S. Panahiyan , S. Fritzsche

We define the quaternionic quantum walk on a finite graph and investigate its properties. This walk can be considered as a natural quaternionic extension of the Grover walk on a graph. We explain the way to obtain all the right eigenvalues…

Quantum Physics · Physics 2016-04-21 Norio Konno , Hideo Mitsuhashi , Iwao Sato

We extend the idea of a discrete-time quantum walk on a graph by placing a qubit on each vertex, and allowing the walker to interact with the qubit at its current position. We show that allowing for a controlled-Z interaction at each time…

Quantum Physics · Physics 2016-08-26 Joshua Lockhart , Mauro Paternostro

Quantum walks have wide applications in quantum information, such as universal quantum computation, so it is important to explore properties of quantum walks thoroughly. We propose a novel method to implement discrete-time quantum walks…

Quantum Physics · Physics 2022-06-09 Qi-Ping Su , Shi-Chao Wang , Yan Chi , Yong-Nan Sun , Li Yu , Zhe Sun , Franco Nori , Chui-Ping Yang

We provide an algorithm that factorizes one-dimensional quantum walks into a protocol of two basic operations: A fixed conditional shift that transports particles between cells and suitable coin operators that act locally in each cell. This…

Quantum Physics · Physics 2025-12-09 C. Cedzich , T. Geib , R. F. Werner

We obtained analytical expressions considering a directed continuous-time quantum walk on a directed infinite line using Bessel functions, expanding previous results in the literature, for a general initial condition. We derive the equation…

Quantum Physics · Physics 2022-08-01 Rodrigo Chaves , Jaime Santos , Bruno Chagas