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Related papers: Perfect State Transfer on Oriented Graphs

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We study pretty good quantum state transfer (i.e., state transfer that becomes arbitrarily close to perfect) between vertices of graphs with an involution in the presence of an energy potential. In particular, we show that if a graph has an…

Combinatorics · Mathematics 2017-02-24 Mark Kempton , Gabor Lippner , Shing-Tung Yau

In this paper we study quantum state transfer (also called quantum tunneling) on graphs when there is a potential function on the vertex set. We present two main results. First, we show that for paths of length greater than three, there is…

Combinatorics · Mathematics 2016-11-11 Mark Kempton , Gabor Lippner , Shing-Tung Yau

The study of perfect state transfer on graphs has attracted a great deal of attention during the past ten years because of its applications to quantum information processing and quantum computation. Perfect state transfer is understood to…

Combinatorics · Mathematics 2023-05-30 Shixin Wang , Tao Feng

Quantum state transfer within a quantum computer can be achieved by using a network of qubits, and such a network can be modelled mathematically by a graph. Here, we focus on the corresponding Laplacian matrix, and those graphs for which…

Quantum Physics · Physics 2022-11-28 Nathaniel Johnston , Steve Kirkland , Sarah Plosker , Rebecca Storey , Xiaohong Zhang

A continuous quantum walk on a graph $X$ with adjacency matrix $A$ is specified by the 1-parameter family of unitary matrices $U(t)=\exp(itA)$. These matrices act on the state space of a quantum system, the states of which we may represent…

Combinatorics · Mathematics 2017-10-12 Chris Godsil

We construct infinite families of graphs in which pretty good state transfer can be induced by adding a potential to the nodes of the graph (i.e. adding a number to a diagonal entry of the adjacency matrix). Indeed, we show that given any…

Combinatorics · Mathematics 2018-04-06 Or Eisenberg , Mark Kempton , Gabor Lippner

We establish the theory for pretty good state transfer in discrete-time quantum walks. For a class of walks, we show that pretty good state transfer is characterized by the spectrum of certain Hermitian adjacency matrix of the graph; more…

Combinatorics · Mathematics 2021-05-11 Ada Chan , Hanmeng Zhan

In this paper, we analyze state transfer in quantum walks by using combinatorial methods. We generalize perfect state transfer in two-reflection discrete-time quantum walks to a notion that we call 'peak state transfer'; we define peak…

Combinatorics · Mathematics 2025-01-14 Krystal Guo , Vincent Schmeits

Quantum walks, an important tool in quantum computing, have been very successfully investigated using techniques in algebraic graph theory. We are motivated by the study of state transfer in continuous-time quantum walks, which is…

Combinatorics · Mathematics 2017-10-09 Chris Godsil , Krystal Guo , Mark Kempton , Gabor Lippner

Perfect quantum state transfer is achievable in different settings, including linear qubit chains, bi-dimensional arrays, ladders, etc. The most studied case contemplates transferring arbitrary one-qubit pure states in systems with…

Quantum Physics · Physics 2026-04-06 Pablo Serra , Alejandro Ferrón , Omar Osenda

This paper investigates perfect state transfer in Grover walks, a model of discrete-time quantum walks. We establish a necessary and sufficient condition for the occurrence of perfect state transfer on graphs belonging to an association…

Combinatorics · Mathematics 2025-06-23 Koushik Bhakta , Bikash Bhattacharjya

We construct families of graphs from linear groups $\mathrm{SL}(2,q)$, $\mathrm{GL}(2,q)$ and $\mathrm{GU}(2,q^2)$, where $q$ is an odd prime power, with the property that the continuous-time quantum walks on the associated networks of…

Combinatorics · Mathematics 2024-08-28 Venkata Raghu Tej Pantangi , Peter Sin

An oriented circulant graph is called integral if all eigenvalues of its Hermitian adjacency matrix are integers. The main purpose of this paper is to investigate the existence of perfect state transfer ($\PST$ for short) and multiple state…

Combinatorics · Mathematics 2022-10-06 Xing-Kun Song

Previously it was shown that (almost) perfect state transfer can be achieved on the complete bipartite graph by a discrete-time coined quantum walk based algorithm when both the sender and receiver vertices are in the same partition of the…

Quantum Physics · Physics 2022-03-09 R. A. M. Santos

We study perfect state transfer on quantum networks represented by weighted graphs. Our focus is on graphs constructed from the join and related graph operators. Some specific results we prove include: (1) The join of a weighted two-vertex…

Quantum Physics · Physics 2010-01-09 R. J. Angeles-Canul , R. Norton , M. Opperman , C. Paribello , M. Russell , C. Tamon

A discrete-time quantum walk is the quantum analogue of a Markov chain on a graph. Zhan [J. Algebraic Combin. 53(4):1187-1213, 2020] proposes a model of discrete-time quantum walk whose transition matrix is given by two reflections, using…

Combinatorics · Mathematics 2022-11-24 Krystal Guo , Vincent Schmeits

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 study perfect state transfer of quantum walks on signed graphs. Our aim is to show that negative edges are useful for perfect state transfer. Specific results we prove include: (1) The signed join of a negative 2-clique with any positive…

Quantum Physics · Physics 2013-01-17 J. Brown , C. Godsil , D. Mallory , A. Raz , C. Tamon

We consider quantum state transfer relative to the Laplacian matrix of a graph. Let $N(u)$ denote the set of all neighbors of a vertex $u$ in a graph $G$. A pair of vertices $u$ and $v$ are called twin vertices of $G$ provided…

Combinatorics · Mathematics 2021-09-14 Hiranmoy Pal

We study perfect state transfer in Grover walks on two important classes of graphs: strongly regular graphs and strongly walk-regular graphs. The latter class is a generalization of the former. We first give a complete classification of…

Combinatorics · Mathematics 2026-02-04 Sho Kubota , Hiroto Sekido , Harunobu Yata , Kiyoto Yoshino