English
Related papers

Related papers: Perfect state transfer on distance-regular graphs …

200 papers

Perfect state transfer and fractional revival can be used to move information between pairs of vertices in a quantum network. While perfect state transfer has received a lot of attention, fractional revival is newer and less studied. One…

Combinatorics · Mathematics 2022-06-14 Chris Godsil , Xiaohong Zhang

For $q\in\mathbb{R}\backslash\{0\}$, the generalized Laplacian of a graph $X$ is the matrix $\mathscr{L}=\Delta+qA$, where $\Delta$ is the degree matrix and $A$ is the adjacency matrix of $X$. In this paper, we investigate perfect state…

Combinatorics · Mathematics 2026-04-23 Swornalata Ojha , Hermie Monterde , Hiranmoy Pal

We consider a discrete-time quantum walk, called the Grover walk, on a distance regular graph $X$. Given that $X$ has diameter $d$ and invertible adjacency matrix, we show that the square of the transition matrix of the Grover walk on $X$…

Combinatorics · Mathematics 2022-10-18 Hanmeng Zhan

The join $X\vee Y$ of two graphs $X$ and $Y$ is the graph obtained by joining each vertex of $X$ to each vertex of $Y$. We explore the behaviour of a continuous quantum walk on a weighted join graph having the adjacency matrix or Laplacian…

Quantum Physics · Physics 2023-12-13 Steve Kirkland , Hermie Monterde

We examine conditions for a pair of strongly cospectral vertices to have pretty good quantum state transfer in terms of minimal polynomials, and provide cases where pretty good state transfer can be ruled out. We also provide new examples…

Quantum Physics · Physics 2020-10-15 Christopher M. van Bommel

We suggest a scheme that allows arbitrarily perfect state transfer even in the presence of random fluctuations in the couplings of a quantum chain. The scheme performs well for both spatially correlated and uncorrelated fluctuations if they…

Quantum Physics · Physics 2007-05-23 Daniel Burgarth , Sougato Bose

Twin vertices in simple unweighted graphs are vertices that have the same neighbours and, in the case of weighted graphs with possible loops, the corresponding incident edges have equal weights. In this paper, we explore the role of twin…

Combinatorics · Mathematics 2023-12-29 Stephen Kirkland , Hermie Monterde , Sarah Plosker

Hitting times are the average time it takes a walk to reach a given final vertex from a given starting vertex. The hitting time for a classical random walk on a connected graph will always be finite. We show that, by contrast, quantum walks…

Quantum Physics · Physics 2009-11-13 Hari Krovi , Todd A. Brun

As generalizations of results of Christandl et al.\cite{8,9""} and Facer et al.\cite{Facer}, Bernasconi et al.\cite{godsil,godsil1} studied perfect state transfer (PST) between two particles in quantum networks modeled by a large class of…

Quantum Physics · Physics 2021-12-29 M. A. Jafarizadeh , R. Sufiania , S. F. Taghavia , E. Barati

Mathematical analysis of the spectral properties of the time evolution operator in quantum walks is essential for understanding key dynamical behaviors such as localization and long-term evolution. The inhomogeneous three-state case, in…

Quantum Physics · Physics 2026-02-05 Chusei Kiumi , Jirô Akahori , Takuya Watanabe , Norio Konno

A weighted graph $G$ with countable vertex set is bounded if there is an upper bound on the maximum of the sum of absolute values of all edge weights incident to a vertex in $G$. In this paper, we prove a fundamental result on equitable…

Combinatorics · Mathematics 2025-10-08 Chris Godsil , Steve Kirkland , Sarojini Mohapatra , Hermie Monterde , Hiranmoy Pal

This paper presents a novel methodology that transforms discrete-time quantum walks into a graph embedding technique, offering a fresh perspective on graph representation methods.Through mathematical manipulations, the approach of this…

Quantum Physics · Physics 2024-07-17 Boxuan Ai

In this article, we consider a spin-spin interaction network governed by $XX + YY$ Hamiltonian. The vertices and edges of the network represent the spin objects and their interactions, respectively. We take a privilege to switch on or off…

Quantum Physics · Physics 2023-02-21 Supriyo Dutta

We show that a perfect quantum state transmission can be realized through a spin chain possessing a commensurate structure of energy spectrum, which is matched with the corresponding parity. As an exposition of the mirror inversion symmetry…

Quantum Physics · Physics 2009-11-10 T. Shi , Ying Li , Z. Song , C. P. Sun

Classical random walks on well-behaved graphs are rapidly mixing towards the uniform distribution. Moore and Russell showed that a continuous quantum walk on the hypercube is instantaneously uniform mixing. We show that the continuous-time…

Quantum Physics · Physics 2007-05-23 Amir Ahmadi , Ryan Belk , Christino Tamon , Carolyn Wendler

The aim of this review paper is to discuss some applications of orthogonal polynomials in quantum information processing. The hope is to keep the paper self contained so that someone wanting a brief introduction to the theory of orthogonal…

Quantum Physics · Physics 2024-12-24 Rachel Bailey

We propose a class of qubit networks that admit perfect state transfer of any two-dimensional quantum state in a fixed period of time. We further show that such networks can distribute arbitrary entangled states between two distant parties,…

We introduce the concept of regular quantum graphs and construct connected quantum graphs with discrete symmetries. The method is based on a decomposition of the quantum propagator in terms of permutation matrices which control the way…

Chaotic Dynamics · Physics 2007-06-13 Simone Severini , Gregor Tanner

We investigate the most general conditions under which a finite ferromagnetic long-range inter- acting spin chain achieves unitary fidelity and the shortest transfer time in transmitting an unknown input qubit. A deeper insight into system…

Quantum Physics · Physics 2009-11-13 Giulia Gualdi , Vojtech Kostak , Irene Marzoli , Paolo Tombesi

We quantify the effect of weighted loops at the source and target nodes of a graph on the strength of quantum state transfer between these vertices. We give lower bounds on loop weights that guarantee strong transfer fidelity that works for…

Quantum Physics · Physics 2024-04-02 Gabor Lippner , Yujia Shi