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Related papers: Generic Quantum Walks with Memory

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Coherent evolution governs the behaviour of all quantum systems, but in nature it is often subjected to influence of a classical environment. For analysing quantum transport phenomena quantum walks emerge as suitable model systems. In…

Continuous-time quantum walks (CTQWs) provide a valuable model for quantum transport, universal quantum computation and quantum spatial search, among others. Recently, the empowering role of new degrees of freedom in the Hamiltonian…

Quantum Physics · Physics 2022-03-23 Massimo Frigerio , Claudia Benedetti , Stefano Olivares , Matteo G. A. Paris

We show that a quantum walk process can be used to construct and secure quantum memory. More precisely, we show that a localized quantum walk with temporal disorder can be engineered to store the information of a single, unknown qubit on a…

Quantum Physics · Physics 2015-04-22 C. M. Chandrashekar , Th. Busch

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

A discrete-time quantum walk (QW) is essentially a unitary operator driving the evolution of a single particle on the lattice. Some QWs have familiar physics PDEs as their continuum limit. Some slight generalization of them (allowing for…

Quantum Physics · Physics 2018-08-22 Pablo Arrighi , Giuseppe Di Molfetta , Stefano Facchini

We introduce a fidelity-based measure $\text{D}_{\text{CQ}}(t)$ to quantify the differences between the dynamics of classical (CW) and quantum (QW) walks over a graph. We provide universal, graph-independent, analytic expressions of this…

Quantum Physics · Physics 2020-07-08 Valentina Gualtieri , Claudia Benedetti , Matteo G. A. Paris

Quantum walks (QWs) describe particles evolving coherently on a lattice. The internal degree of freedom corresponds to a Hilbert space, called coin system. We consider QWs on Cayley graphs of some group $G$. In the literature,…

The quantum walk (QW) was introduced as a quantum counterpart of the classical random walk. A number of non-classical properties of the QW have been shown, e.g., ballistic spreading, anti-bellshaped limit density, localization. Since around…

Quantum Physics · Physics 2019-05-07 Norio Konno

Quantum Random Access Memory (QRAM) has the potential to revolutionize the area of quantum computing. QRAM uses quantum computing principles to store and modify quantum or classical data efficiently, greatly accelerating a wide range of…

Quantum Physics · Physics 2023-05-03 Koustubh Phalak , Avimita Chatterjee , Swaroop Ghosh

Quantum Stochastic Walks (QSW) allow for a generalization of both quantum and classical random walks by describing the dynamic evolution of an open quantum system on a network, with nodes corresponding to quantum states of a fixed basis. We…

Quantum Physics · Physics 2020-03-31 Nicola Dalla Pozza , Filippo Caruso

We study how quantum walks can be used to find structural anomalies in graphs via several examples. Two of our examples are based on star graphs, graphs with a single central vertex to which the other vertices, which we call external…

Quantum Physics · Physics 2015-06-05 Mark Hillery , Hongjun Zheng , Edgar Feldman , Daniel Reitzner , Vladimir Buzek

Quantum walks, both discrete (coined) and continuous time, form the basis of several quantum algorithms and have been used to model processes such as transport in spin chains and quantum chemistry. The enhanced spreading and mixing…

Quantum Physics · Physics 2010-12-10 Godfrey Leung , Paul Knott , Joe Bailey , Viv Kendon

We formulate three current models of discrete-time quantum walks in a combinatorial way. These walks are shown to be closely related to rotation systems and 1-factorizations of graphs. For two of the models, we compute the traces and total…

Combinatorics · Mathematics 2019-05-17 Chris Godsil , Hanmeng Zhan

Rules for quantizing the walker+coin parts of a classical random walk are provided by treating them as interacting quantum systems. A quantum optical random walk (QORW), is introduced by means of a new rule that treats quantum or classical…

Quantum Physics · Physics 2009-11-13 Demosthenes Ellinas , Ioannis Smyrnakis

The CGMV method allows for the general discussion of localization properties for the states of a one-dimensional quantum walk, both in the case of the integers and in the case of the non negative integers. Using this method we classify,…

Quantum Physics · Physics 2010-10-28 M. J. Cantero , F. A. Grunbaum , L. Moral , L. Velazquez

Quantum and random walks have been shown to be equivalent in the following sense: a time-dependent random walk can be constructed such that its vertex distribution at all time instants is identical to the vertex distribution of any…

Quantum Physics · Physics 2023-06-13 Matheus G. Andrade , Franklin de Lima Marquezino , Daniel R. Figueiredo

Quantum walks, both discrete and continuous, serve as fundamental tools in quantum information processing with diverse applications. This work introduces a hybrid quantum walk model that integrates the coin mechanism of discrete walks with…

Quantum Physics · Physics 2025-09-12 Tianen Chen , Yun Shang

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

We solve an open problem by constructing quantum walks that not only detect but also find marked vertices in a graph. In the case when the marked set $M$ consists of a single vertex, the number of steps of the quantum walk is quadratically…

Quantum Physics · Physics 2016-03-01 Hari Krovi , Frédéric Magniez , Maris Ozols , Jérémie Roland

Quantum walks (QWs) have a property that classical random walks (RWs) do not possess -- the coexistence of linear spreading and localization -- and this property is utilized to implement various kinds of applications. This paper proposes…