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Related papers: Quantum Search with the Signless Laplacian

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The idea that the search efficiency can be increased with the help of a number of autonomous agents is often relevant in many situations, which is known among biologists and roboticists as a stigmergy. This is due to the fact that, in any…

Quantum Physics · Physics 2019-09-17 Jin-Hui Zhu , Li-Hua Lu , You-Quan Li

Given the extensive application of classical random walks to classical algorithms in a variety of fields, their quantum analogue in quantum walks is expected to provide a fruitful source of quantum algorithms. So far, however, such…

Quantum Physics · Physics 2008-03-26 B. L. Douglas , J. B. Wang

Quantum walks generated by the adjacency matrix or the Laplacian are known to exhibit low transfer fidelity on general graphs. In this paper, we study continuous-time quantum walks governed by the generalized Laplacian operator L_k = A+kD,…

Quantum Physics · Physics 2025-10-13 Yujia Shi

We make and generalize the observation that summing of probability amplitudes of a discrete-time quantum walk over partitions of the walking graph consistent with the step operator results in a unitary evolution on the reduced graph which…

Quantum Physics · Physics 2020-04-06 Václav Potoček

Let $X$ be a weighted graph and $M$ be its adjacency, Laplacian or signless Laplacian matrix. In a continuous quantum walk on $X$, local $\epsilon$-uniform mixing occurs at vertex $u$ if the $u$th column of the matrix $U(t)=e^{itM}$ can be…

Combinatorics · Mathematics 2026-03-24 Hermie Monterde

Quantum walk search may exhibit phenomena beyond the intuition from a conventional random walk theory. One of such examples is exceptional configuration phenomenon -- it appears that it may be much harder to find any of two or more marked…

Quantum Physics · Physics 2021-01-13 Adam Glos , Nikolajs Nahimovs , Konstantin Balakirev , Kamil Khadiev

In this paper, we consider continuous-time quantum walks (CTQWs) on finite graphs determined by the Laplacian matrices. By introducing fully interconnected graph decomposition of given graphs, we show a decomposition method for the…

Quantum Physics · Physics 2015-04-20 Yusuke Ide

We study the quantum walk search algorithm of Shenvi, Kempe and Whaley [PRA 67 052307 (2003)] on data structures of one to two spatial dimensions, on which the algorithm is thought to be less efficient than in three or more spatial…

Quantum Physics · Physics 2010-10-25 Neil B. Lovett , Matthew Everitt , Matthew Trevers , Daniel Mosby , Dan Stockton , Viv Kendon

We study the set of probability distributions visited by a continuous-time quantum walk on graphs. An edge-weighted graph G is universal mixing if the instantaneous or average probability distribution of the quantum walk on G ranges over…

Quantum Physics · Physics 2008-06-13 W. Carlson , A. Ford , E. Harris , J. Rosen , C. Tamon , K. Wrobel

Quantum walks, both discrete (coined) and continuous time, on a general graph of N vertices with undirected edges are reviewed in some detail. The resource requirements for implementing a quantum walk as a program on a quantum computer are…

Quantum Physics · Physics 2007-05-23 Viv Kendon

When searching for a marked vertex in a graph, Szegedy's usual search operator is defined by using the transition probability matrix of the random walk with absorbing barriers at the marked vertices. Instead of using this operator, we…

Quantum Physics · Physics 2016-04-13 Raqueline A. M. Santos

There are presently two models for quantum walks on graphs. The "coined" walk uses discrete time steps, and contains, besides the particle making the walk, a second quantum system, the coin, that determines the direction in which the…

Quantum Physics · Physics 2009-11-10 Mark Hillery , Janos Bergou , Edgar Feldman

Quantum walk has emerged as an essential tool for searching marked vertices on various graphs. Recent advances in the discrete-time quantum walk search algorithm have enabled it to effectively handle multiple marked vertices, expanding its…

Quantum Physics · Physics 2025-10-07 Pulak Ranjan Giri , Rei Sato , Kazuhiro Saito

Quantum search on the two-dimensional lattice with one marked vertex and cyclic boundary conditions is an important problem in the context of quantum algorithms with an interesting unfolding. It avails to test the ability of quantum walk…

Quantum Physics · Physics 2017-05-03 Renato Portugal , Tharso D. Fernandes

Recently, Braunstein et al. [1] introduced normalized Laplacian matrices of graphs as density matrices in quantum mechanics and studied the relationships between quantum physical properties and graph theoretical properties of the underlying…

Quantum Physics · Physics 2011-11-15 Chai Wah Wu

Continuous-time quantum walks (CTQW) have shown the capability to perform efficiently the spatial search of a marked site on many kinds of graphs. However, most of such graphs are hard to realize in an experimental setting. Here we study…

Quantum Physics · Physics 2021-12-08 C. Benedetti , D. Tamascelli , M. G. A. Paris , A. Crespi

We present a continuous-time quantum search algorithm on a graphene lattice. This provides the sought-after implementation of an efficient continuous-time quantum search on a two-dimensional lattice. The search uses the linearity of the…

Quantum Physics · Physics 2015-06-18 Iain Foulger , Sven Gnutzmann , Gregor Tanner

We study whether the probability distribution of a discrete quantum walk can get arbitrarily close to uniform, given that the walk starts with a uniform superposition of the outgoing arcs of some vertex. We establish a characterization of…

Combinatorics · Mathematics 2024-07-03 Hanmeng Zhan

We investigate quantum and nonsignaling generalizations of perfect matchings in graphs using nonlocal games. Specifically, we introduce nonlocal games that test for $L$-perfect matchings in bipartite graphs, perfect matchings in general…

Quantum Physics · Physics 2025-02-10 David Cui , Laura Mančinska , Seyed Sajjad Nezhadi , David E. Roberson

With the constant flow of data from vast sources over the past decades, a plethora of advanced analytical techniques have been developed to extract relevant information from different data types ranging from labeled data, quasi-labeled…

Quantum Physics · Physics 2025-11-07 Andrew Vlasic , Anh Pham