English
Related papers

Related papers: Szegedy Walk Unitaries for Quantum Maps

200 papers

Szegedy's quantum walk gives a generic quadratic speedup for reversible classical Markov chains, but extending this mechanism to quantum Gibbs sampling has remained challenging beyond special cases. We present a walk-free quantum algorithm…

Quantum Physics · Physics 2026-04-28 Jiaqi Leng , Jiaqing Jiang , Lin Lin

Quantum walks with memory(QWM) are a type of modified quantum walks that record the walker's latest path. The general model of coined QWM is presented in Phys. Rev. A 93, 042323 (2016). In this paper, we present general model of Szegedy…

Quantum Physics · Physics 2019-05-03 Dan Li , Ying Liu , Yu-Guang Yang , Juan Xu , Jia-Bing Yuan

We define quantization scheme for discrete-time random walks on the half-line consistent with Szegedy's quantization of finite Markov chains. Motivated by the Karlin and McGregor description of discrete-time random walks in terms of…

Mathematical Physics · Physics 2025-10-03 Adam Doliwa , Artur Siemaszko

The study of quantum walks has been shown to have a wide range of applications in areas such as artificial intelligence, the study of biological processes, and quantum transport. The quantum stochastic walk, which allows for incoherent…

Quantum Physics · Physics 2020-02-20 Luke C. G. Govia , Bruno G. Taketani , Peter K. Schuhmacher , Frank K. Wilhelm

We present an idea to convert to a unitary quantum walk any open quantum walk which is defined on lattices as well as on finite graphs. This approach generalizes to the domain of open quantum walks (or quantum Markov chains) the framework…

Quantum Physics · Physics 2015-02-06 Chaobin Liu

We present a detailed circuit implementation of Szegedy's quantization of the Metropolis-Hastings walk. This quantum walk is usually defined with respect to an oracle. We find that a direct implementation of this oracle requires costly…

Quantum Physics · Physics 2020-07-01 Jessica Lemieux , Bettina Heim , David Poulin , Krysta Svore , Matthias Troyer

Quantum walks are recognizably useful for the development of new quantum algorithms, as well as for the investigation of several physical phenomena in quantum systems. Actual implementations of quantum walks face technological difficulties…

Quantum Physics · Physics 2017-01-31 Renato Portugal , Marcos Cesar de Oliveira , Jalil Khatibi Moqadam

The quantum walk is a powerful tool to develop quantum algorithms, which usually are based on searching for a vertex in a graph with multiple marked vertices, Ambainis's quantum algorithm for solving the element distinctness problem being…

Quantum Physics · Physics 2022-12-21 G. A. Bezerra , P. H. G. Lugão , R. Portugal

A number of recent studies have investigated the introduction of decoherence in quantum walks and the resulting transition to classical random walks. Interestingly, it has been shown that algorithmic properties of quantum walks with…

Quantum Physics · Physics 2016-01-19 Andrea Torsello , Luca Rossi

This study investigates unitary equivalent classes of one-dimensional quantum walks. We prove that one-dimensional quantum walks are unitary equivalent to quantum walks of Ambainis type and that translation-invariant one-dimensional quantum…

Mathematical Physics · Physics 2016-03-21 Hiromichi Ohno

Random walk algorithms are crucial for sampling and approximation problems in statistical physics and theoretical computer science. The mixing property is necessary for Markov chains to approach stationary distributions and is facilitated…

Quantum Physics · Physics 2024-12-02 Shyam Dhamapurkar , Yuhang Dang , Saniya Wagh , Xiu-Hao Deng

Testing graph completeness is a critical problem in computer science and network theory. Leveraging quantum computation, we present an efficient algorithm using the Szegedy quantum walk and quantum phase estimation (QPE). Our algorithm,…

Quantum Physics · Physics 2025-11-26 Sara Giordano , Miguel A. Martin-Delgado

Quantum walks provide a powerful framework for achieving algorithmic speedup in quantum computing. This paper presents a quantum search algorithm for 2-tessellable graphs, a generalization of bipartite graphs, achieving a quadratic speedup…

Quantum Physics · Physics 2025-04-18 Gustavo Alves Bezerra , Andris Ambainis , Renato Portugal

We propose a twisted Szegedy walk for estimating the limit behavior of a discrete-time quantum walk on a crystal lattice, an infinite abelian covering graph, whose notion was introduced by [14]. First, we show that the spectrum of the…

Probability · Mathematics 2014-10-23 Yusuke Higuchi , Norio Konno , Iwao Sato , Etsuo Segawa

We present an efficient general method for realizing a quantum walk operator corresponding to an arbitrary sparse classical random walk. Our approach is based on Grover and Rudolph's method for preparing coherent versions of efficiently…

Quantum Physics · Physics 2013-06-12 Chen-Fu Chiang , Daniel Nagaj , Pawel Wocjan

Quantum walks, the quantum analogue of the classical random walk, have been shown to underpin quantum algorithms for fluid dynamics. We propose the quantum half-adder gate method for quantum walks as a good benchmark algorithm, specifically…

Quantum Physics · Physics 2026-04-17 Steph Foulds , Viv Kendon

We consider the Szegedy walk on graphs adding infinite length tails to a finite internal graph. We assume that on these tails, the dynamics is given by the free quantum walk. We set the $\ell^\infty$-category initial state so that the…

Quantum Physics · Physics 2020-08-26 Yusuke Higuchi , Mohamed Sabri , Etsuo Segawa

We analyze the equivalence between discrete-time coined quantum walks and Szegedy's quantum walks. We characterize a class of flip-flop coined models with generalized Grover coin on a graph $\Gamma$ that can be directly converted into…

Quantum Physics · Physics 2017-05-03 Renato Portugal , Etsuo Segawa

Universal quantum computation can be realised using both continuous-time and discrete-time quantum walks. We present a version based on single particle discrete-time quantum walk to realize multi-qubit computation tasks. The scalability of…

Quantum Physics · Physics 2023-08-21 Prateek Chawla , Shivani Singh , Aman Agarwal , Sarvesh Srinivasan , C. M. Chandrashekar

Recently, the idea of classical Metropolis sampling through Markov chains has been generalized for quantum Hamiltonians. However, the underlying Markov chain of this algorithm is still classical in nature. Due to Szegedy's method, the…

Quantum Physics · Physics 2012-03-07 Man-Hong Yung , Alán Aspuru-Guzik