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Related papers: From open quantum walks to unitary quantum walks

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In this work we study certain aspects of Open Quantum Random Walks (OQRWs), a class of quantum channels described by S. Attal et al. \cite{attal}. As a first objective we consider processes which are nonhomogeneous in time, i.e., at each…

Mathematical Physics · Physics 2016-08-10 Carlos F. Lardizabal , Rafael R. Souza

Quantum Cryptography is a rapidly developing field of research that benefits from the properties of Quantum Mechanics in performing cryptographic tasks. Quantum walks are a powerful model for quantum computation and very promising for…

Quantum Physics · Physics 2016-02-04 C. Vlachou , J. Rodrigues , P. Mateus , N. Paunković , A. Souto

Describing a particle in an external electromagnetic field is a basic task of quantum mechanics. The standard scheme for this is known as "minimal coupling", and consists of replacing the momentum operators in the Hamiltonian by modified…

Quantum Physics · Physics 2019-01-29 C. Cedzich , T. Geib , A. H. Werner , R. F. Werner

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 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

The discrete-time quantum walk (QW) has been extensively and intensively investigated for the last decade, whose coin operator is defined by a unitary matrix. We extend the QW to a walk determined by a unitary matrix whose component is…

Quantum Physics · Physics 2015-05-05 Norio Konno

We consider a model of open quantum random walk and together with a quantum trajectory approach we are able to examine a notion of hitting time. We see that many constructions, such as minimal solutions to hitting time problems, are…

Mathematical Physics · Physics 2016-08-10 Carlos F. Lardizabal

A continuous-time quantum walk is modelled using a graph. In this short paper, we provide lower bounds on the size of a graph that would allow for some quantum phenomena to occur. Among other things, we show that, in the adjacency matrix…

Combinatorics · Mathematics 2018-05-23 Gabriel Coutinho

We investigate the quantum versions of a one-dimensional random walk, whose corresponding Markov Chain is of order 2. This corresponds to the walk having a memory of up to two previous steps. We derive the amplitudes and probabilities for…

Quantum Physics · Physics 2010-05-02 Michael McGettrick

A simple coined quantum walk in one dimension can be characterized by a $SU(2)$ operator with three parameters which represents the coin toss. However, different such coin toss operators lead to equivalent dynamics of the quantum walker. In…

Quantum Physics · Physics 2014-12-04 Sandeep K Goyal , Thomas Konrad , Lajos Diósi

It is demonstrated that in gate-based quantum computing architectures quantum walk is a natural mathematical description of quantum gates. It originates from field-matter interaction driving the system, but is not attached to specific qubit…

Quantum Physics · Physics 2020-05-08 Dmitry Solenov

Quantum random walks, - coined, lattice ones, - exhibit ballistic behavior with fascinating asymptotic patterns of the amplitudes. We show that averaging over the coins (using the Haar measure), these patterns blend into a spline. Also, we…

Mathematical Physics · Physics 2021-08-11 Yuliy Baryshnikov

In this paper, we propose an extension of quantum searches on graphs driven by quantum walks to simplicial complexes. To this end, we newly define a quantum walk on simplicial complex which is an alternative of preceding studies by authors.…

Mathematical Physics · Physics 2017-12-06 Kaname Matsue , Osamu Ogurisu , Etsuo Segawa

In this paper we study convergence of random walks, on finite quantum groups, arising from linear combination of irreducible characters. We bound the distance to the Haar state and determine the asymptotic behavior, i.e. the limit state if…

Quantum Algebra · Mathematics 2019-05-14 Isabelle Baraquin

In this work we focus on the notion of quantum hitting time for discrete-time Szegedy quantum walks, compared to its classical counterpart. Under suitable hypotheses, quantum hitting time is known to be of the order of the square root of…

Quantum Physics · Physics 2024-09-18 P. Boito , G. M. Del Corso

In this work, we generalize the recently-introduced graph composition framework to the non-boolean setting. A quantum algorithm in this framework is represented by a hypergraph, where each hyperedge is adjacent to multiple vertices. The…

Quantum Physics · Physics 2025-10-07 Arjan Cornelissen

Let $X$ be a graph with adjacency matrix $A$. The \textsl{continuous quantum walk} on $X$ is determined by the unitary matrices $U(t)=\exp(itA)$. If $X$ is the complete graph $K_n$ and $a\in V(X)$, then \[1-|U(t)_{a,a}|\le2/n. \] In a…

Combinatorics · Mathematics 2017-11-01 Chris Godsil

Quantum walks have emerged as a transformative paradigm in quantum information processing and can be applied to various graph problems. This study explores discrete-time quantum walks on simplicial complexes, a higher-order generalization…

Quantum Physics · Physics 2024-05-24 Euijun Song

We explore a discrete-time, coined quantum walk on a quantum network where the coherent superposition of walker-moves originates from the unitary interaction of the walker-coin with the qubit degrees of freedom in the quantum network. The…

Quantum Physics · Physics 2024-06-04 Jigyen Bhavsar , Shashank Shekhar , Siddhartha Santra

We analyze final-time dependent discrete-time quantum walks in one dimension. We compute asymptotics of the return probability of the quantum walk by a path counting approach. Moreover, we discuss a relation between the quantum walk and the…

Quantum Physics · Physics 2011-09-21 Yusuke Ide , Norio Konno , Takuya Machida , Etsuo Segawa