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Related papers: Tuning for Quantum Speedup in Directed Lackadaisic…

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Up to now, relatively few exponential quantum speed-ups have been achieved. Out of them, the welded tree problem (Childs, Cleve, Deotto, Farhi, Gutmann, and Spielman'2003) is one of the unusual examples, as the exponential speed-up is…

Quantum Physics · Physics 2024-05-01 Aleksandrs Belovs

Quantum walks are a powerful framework for the development of quantum algorithms, with lackadaisical quantum walks (LQWs) standing out as an efficient model for spatial search. In this work, we investigate how broken-link decoherence…

For a continuous-time quantum walk on a line the variance of the position observable grows quadratically in time, whereas, for its classical counterpart on the same graph, it exhibits a linear, diffusive, behaviour. A quantum walk, thus,…

Quantum Physics · Physics 2008-01-30 Diego de Falco , Dario Tamascelli

We compare discrete-time quantum walks on graphs to their natural classical equivalents, which we argue are lifted Markov chains, that is, classical Markov chains with added memory. We show that these can simulate quantum walks, allowing us…

Quantum Physics · Physics 2018-09-26 Simon Apers , Alain Sarlette , Francesco Ticozzi

Continuous-time quantum walks provide a natural framework to tackle the fundamental problem of finding a node among a set of marked nodes in a graph, known as spatial search. Whether spatial search by continuous-time quantum walk provides a…

Quantum Physics · Physics 2022-10-24 Simon Apers , Shantanav Chakraborty , Leonardo Novo , Jérémie Roland

Quantum versions of random walks on the line and the cycle show a quadratic improvement over classical random walks in their spreading rates and mixing times respectively. Non-unitary quantum walks can provide a useful optimisation of these…

Quantum Physics · Physics 2008-03-25 Viv Kendon , Olivier Maloyer

The quantum walk (QW) is the term given to a family of algorithms governing the evolution of a discrete quantum system and as such has a founding role in the study of quantum computation. We contribute to the investigation of QW phenomena…

Quantum Physics · Physics 2015-07-02 Hao Luo , Peng Xue

When confined to a topological environment consisting of a cycle coupled with a half-line, quantum walks exhibit long-term statistical tendencies which differ dramatically from the tendencies of classical random walks in the same…

Quantum Physics · Physics 2015-06-08 Forrest Ingram-Johnson , Chaobin Liu , Nelson Petulante

In a Quantum Walk (QW) the "walker" follows all possible paths at once through the principle of quantum superposition, differentiating itself from classical random walks where one random path is taken at a time. This facilitates the…

Quantum walks, being the quantum analogue of classical random walks, are expected to provide a fruitful source of quantum algorithms. A few such algorithms have already been developed, including the `glued trees' algorithm, which provides…

Quantum Physics · Physics 2009-10-29 B. L. Douglas , J. B. Wang

Full control over the dynamics of interacting, indistinguishable quantum particles is an important prerequisite for the experimental study of strongly correlated quantum matter and the implementation of high-fidelity quantum information…

A discrete time quantum walk is considered in which the step lengths are chosen to be either $1$ or $2$ with the additional feature that the walker is persistent with a probability $p$. This implies that with probability $p$, the walker…

Quantum Physics · Physics 2020-04-08 Suchetana Mukhopadhyay , Parongama Sen

We study the effects of interparticle interactions and power-law tunneling couplings on quantum walks executed by both a single one and a pair of hard-core bosons moving in clean and disordered one-dimensional lattices. For this purpose, we…

Quantum Gases · Physics 2021-09-15 G. A. Domínguez-Castro , R. Paredes

We characterize quantumness of the so-called quantum walks (whose dynamics is governed by quantum mechanics) by introducing two computable measures which are stronger than the variance of the walker's position probability distribution. The…

Quantum Physics · Physics 2018-10-09 F. Shahbeigi , S. J. Akhtarshenas , A. T. Rezakhani

Quantum walks are at the heart of modern quantum technologies. They allow to deal with quantum transport phenomena and are an advanced tool for constructing novel quantum algorithms. Quantum walks on graphs are fundamentally different from…

Quantum Physics · Physics 2019-12-18 Alexey A. Melnikov , Leonid E. Fedichkin , Alexander Alodjants

Quantum walk is one of the main tools for quantum algorithms. Defined by analogy to classical random walk, a quantum walk is a time-homogeneous quantum process on a graph. Both random and quantum walks can be defined either in continuous or…

Quantum Physics · Physics 2010-01-10 Andrew M. Childs

Quantum walk research has mainly focused on evolutions due to repeated applications of time-independent unitary coin operators. However, the idea of controlling the single particle evolution using time-dependent unitary coins has still been…

Quantum Physics · Physics 2019-09-19 Shrabanti Dhar , Abdul Khaleque , Tushar Kanti Bose

Random walks simulate the randomness of objects, and are key instruments in various fields such as computer science, biology and physics. The counter part of classical random walks in quantum mechanics are the quantum walks. Quantum walk…

Social and Information Networks · Computer Science 2023-01-09 Annamaria Ficara , Giacomo Fiumara , Pasquale De Meo , Salvatore Catanese

A discrete-time Quantum Walk (QW) is essentially a unitary operator driving the evolution of a single particle on the lattice. Some QWs admit a continuum limit, leading to familiar PDEs (e.g. the Dirac equation). In this paper, we study the…

Quantum Physics · Physics 2016-04-29 Pablo Arrighi , Stefano Facchini , Marcelo Forets

Incorporating higher-order interactions in information processing enables us to build more accurate models, gain deeper insights into complex systems, and address real-world challenges more effectively. However, existing methods, such as…

Quantum Physics · Physics 2024-04-25 Ryu Hayakawa , Kuo-Chin Chen , Min-Hsiu Hsieh