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Related papers: Continuous Time Quantum Walks in finite Dimensions

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There exist several types of configurations of marked vertices, referred to as the exceptional configurations, on one- and two-dimensional periodic lattices with additional long-range edges of the Hanoi network of degree four (HN4), which…

Quantum Physics · Physics 2026-02-09 Satoshi Watanabe , Pulak Ranjan Giri

A randomly walking quantum particle evolving by Schr\"odinger's equation searches on $d$-dimensional cubic lattices in $O(\sqrt{N})$ time when $d \ge 5$, and with progressively slower runtime as $d$ decreases. This suggests that graph…

Quantum Physics · Physics 2015-03-20 David A. Meyer , Thomas G. Wong

We investigate a quantum spatial search problem on a fractal lattice. A recent study for the Sierpinski gasket and tetrahedron made a conjecture that the dynamics of the search on a fractal lattice is determined by spectral dimension. We…

Quantum Physics · Physics 2018-07-31 Shu Tamegai , Shohei Watabe , Tetsuro Nikuni

This work examines the time complexity of quantum search algorithms on combinatorial $t$-designs with multiple marked elements using the continuous-time quantum walk. Through a detailed exploration of $t$-designs and their incidence…

Quantum Physics · Physics 2025-04-08 Pedro H. G. Lugão , Renato Portugal

In network science, graphs obtained by taking the Kronecker or tensor power of the adjacency matrix of an initiator graph are used to construct complex networks. In this paper, we analytically prove sufficient conditions under which such…

Quantum Physics · Physics 2018-12-31 Adam Glos , Thomas G. Wong

In the typical model, a discrete-time coined quantum walk searching the 2D grid for a marked vertex achieves a success probability of $O(1/\log N)$ in $O(\sqrt{N \log N})$ steps, which with amplitude amplification yields an overall runtime…

Quantum Physics · Physics 2018-02-15 Thomas G. Wong

In this survey paper we give an intuitive treatment of the discrete time quantization of classical Markov chains. Grover search and the quantum walk based search algorithms of Ambainis, Szegedy and Magniez et al. will be stated as quantum…

Quantum Physics · Physics 2008-08-04 Miklos Santha

The spatial search problem aims to find a marked vertex of a finite graph using a dynamic with two constraints: (1) The walker has no compass and (2) the walker can check whether a vertex is marked only after reaching it. This problem is a…

Quantum Physics · Physics 2022-06-02 Hajime Tanaka , Mohamed Sabri , Renato Portugal

We show a simple generalization of the quantum walk algorithm for search in backtracking trees by Montanaro (ToC 2018) to the case where vertices can have different times of computation. If a vertex $v$ in the tree of depth $D$ is computed…

Quantum Physics · Physics 2025-11-25 Jevgēnijs Vihrovs

With the growing interest in quantum machine learning, the perceptron -- a fundamental building block in traditional machine learning -- has emerged as a valuable model for exploring quantum advantages. Two quantum perceptron algorithms…

Quantum Physics · Physics 2025-03-24 Xiaoyu Sun , Mathieu Roget , Giuseppe Di Molfetta , Hachem Kadri

We show how to search N items arranged on a $\sqrt{N}\times\sqrt{N}$ grid in time $O(\sqrt N \log N)$, using a discrete time quantum walk. This result for the first time exhibits a significant difference between discrete time and continuous…

Quantum Physics · Physics 2007-05-23 Andris Ambainis , Julia Kempe , Alexander Rivosh

We study the average probability that a discrete-time quantum walk finds a marked vertex on a graph. We first show that, for a regular graph, the spectrum of the transition matrix is determined by the weighted adjacency matrix of an…

Combinatorics · Mathematics 2021-08-24 Hanmeng Zhan

We investigate a quantum spatial search problem on fractal lattices, such as Sierpinski carpets and Menger sponges. In earlier numerical studies of the Sierpinski gasket, the Sierpinski tetrahedron, and the Sierpinski carpet, conjectures…

Quantum Physics · Physics 2020-02-19 Rei Sato , Tetsuro Nikuni , Shohei Watabe

Continuous-time quantum walks are typically effected by either the discrete Laplacian or the adjacency matrix. In this paper, we explore a third option: the signless Laplacian, which has applications in algebraic graph theory and may arise…

Quantum Physics · Physics 2025-03-26 Molly E. McLaughlin , Thomas G. Wong

A randomly walking quantum particle evolving by Schr\"odinger's equation searches for a unique marked vertex on the "simplex of complete graphs" in time $\Theta(N^{3/4})$. In this paper, we give a weighted version of this graph that…

Quantum Physics · Physics 2015-09-22 Thomas G. Wong

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 identify a key difference between quantum search by discrete- and continuous-time quantum walks: a discrete-time walk typically performs one walk step per oracle query, whereas a continuous-time walk can effectively perform multiple walk…

Quantum Physics · Physics 2015-08-24 Thomas G. Wong , Andris Ambainis

The lackadaisical quantum walk is a lazy version of a discrete-time, coined quantum walk, where each vertex has a weighted self-loop that permits the walker to stay put. They have been used to speed up spatial search on a variety of graphs,…

Quantum Physics · Physics 2022-01-20 Jacob Rapoza , Thomas G. Wong

Lackadaisical quantum walk(LQW) has been an efficient technique in searching a target state from a database which is distributed on a two-dimensional lattice. We numerically study the quantum search algorithm based on the lackadaisical…

Quantum Physics · Physics 2019-12-04 Pulak Ranjan Giri , Vladimir Korepin

We provide numerical evidence that the nonlinear searching algorithm introduced by Wong and Meyer \cite{meyer2013nonlinear}, rephrased in terms of quantum walks with effective nonlinear phase, can be extended to the finite 2-dimensional…

Quantum Physics · Physics 2020-11-16 Basile Herzog , Giuseppe Di Molfetta