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Related papers: Quantum state transfer on Q-graphs

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This work deals with quantum transport in open quantum graphs. We consider the case of complete graphs on $n$ vertices with an edge removed and attached to two leads, to represent the entrance and exit channels, from where we calculate the…

Quantum Physics · Physics 2024-12-23 Alison A. Silva , D. Bazeia , Fabiano M. Andrade

This paper discusses continuous-time quantum walks and asymptotic state transfer in graphs with an involution. By providing quantitative bounds on the eigenvectors of the Hamiltonian, it provides an approach to achieving high-fidelity state…

Quantum Physics · Physics 2023-10-16 Gabor Lippner , Yujia Shi

An $s$-pair state in a graph is a quantum state of the form $\mathbf{e}_u+s\mathbf{e}_v$, where $u$ and $v$ are vertices in the graph and $s$ is a non-zero complex number. If $s=-1$ (resp., $s=1$), then such a state is called a pair state…

Quantum Physics · Physics 2024-07-30 Sooyeong Kim , Hermie Monterde , Bahman Ahmadi , Ada Chan , Stephen Kirkland , Sarah Plosker

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

Perfect state transfer between qubits on a uniformly coupled network, with interactions specified by a graph, has advantages over an engineered chain, such as much faster transfer times (independent of the distance between the input and…

Quantum Physics · Physics 2018-11-27 Alastair Kay

We introduce the concept of group state transfer on graphs, summarize its relationship to other concepts in the theory of quantum walks, set up a basic theory, and discuss examples. Let $X$ be a graph with adjacency matrix $A$ and consider…

Quantum Physics · Physics 2021-03-17 Luke C. Brown , William J. Martin , Duncan Wright

The existence of perfect state transfer (PST) on quantum spin networks is a fundamental problem in mathematics and physics. Various works in the literature have explored PST in graphs with arithmetic origins, such as gcd-graphs over…

Combinatorics · Mathematics 2025-04-02 Tung T. Nguyen , Nguyen Duy Tân

For a graph $G$ and a related symmetric matrix $M$, the continuous-time quantum walk on $G$ relative to $M$ is defined as the unitary matrix $U(t) = \exp(-itM)$, where $t$ varies over the reals. Perfect state transfer occurs between…

Quantum Physics · Physics 2016-05-10 R. Alvir , S. Dever , B Lovitz , J. Myer , C. Tamon , Y. Xu , H. Zhan

The ability to accurately transfer quantum information through networks is an important primitive in distributed quantum systems. While perfect quantum state transfer (PST) can be effected by a single particle undergoing continuous-time…

Quantum Physics · Physics 2015-04-01 Steven J. Large , Michael S. Underwood , David L. Feder

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

A continuous-time quantum walk on a graph is a matrix-valued function $\exp(-\mathtt{i} At)$ over the reals, where $A$ is the adjacency matrix of the graph. Such a quantum walk has universal perfect state transfer if for all vertices $u,v$,…

Quantum Physics · Physics 2017-01-20 Erin Connelly , Nathaniel Grammel , Michael Kraut , Luis Serazo , Christino Tamon

Perfect state transfer (PST) has great significance due to its applications in quantum information processing and quantum computation. In this paper we present a characterization on connected simple Cayley graph $\Gamma={\rm Cay}(G,S)$…

Quantum Physics · Physics 2017-12-27 Yingying Tan , Keqin Feng , Xiwang Cao

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

A continuous-time quantum random walk describes the motion of a quantum mechanical particle on an underlying graph. The graph itself is associated with a Hilbert space of dimension equal to the number of vertices. The dynamics of the walk…

Quantum Physics · Physics 2021-09-28 Jaideep Mulherkar , Rishikant Rajdeepak , V. Sunitha

If $X$ is a graph with adjacency matrix $A$, then we define $H(t)$ to be the operator $\exp(itA)$. We say that we have perfect state transfer in $X$ from the vertex $u$ to the vertex $v$ at time $\tau$ if the $uv$-entry of…

Combinatorics · Mathematics 2017-06-20 Chris Godsil

For any graph $X$ with the adjacency matrix $A$, the transition matrix of the continuous-time quantum walk at time $t$ is given by the matrix-valued function $\mathcal{H}_X(t)=\mathrm{e}^{itA}$. We say that there is perfect state transfer…

Combinatorics · Mathematics 2018-04-17 Bahman Ahmadi , M. H. Shirdareh Haghighi , Ahmad Mokhtar

Perfect state transfer in graphs is a concept arising from quantum physics and quantum computing. Given a graph $G$ with adjacency matrix $A_G$, the transition matrix of $G$ with respect to $A_G$ is defined as $H_{A_{G}}(t) =…

Combinatorics · Mathematics 2020-10-08 Yipeng Li , Xiaogang Liu , Shenggui Zhang , Sanming Zhou

We introduce and study peak state transfer, a notion of high state transfer in qubit networks modeled by continuous-time quantum walks. Unlike perfect or pretty good state transfer, peak state transfer does not require fidelity arbitrarily…

Quantum Physics · Physics 2025-10-02 Gabriel Coutinho , Krystal Guo , Vincent Schmeits

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

In this paper we answer the question of when circulant quantum spin networks with nearest-neighbor couplings can give perfect state transfer. The network is described by a circulant graph $G$, which is characterized by its circulant…

Discrete Mathematics · Computer Science 2011-04-12 Milan Bašić