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We address the performance of a coin-biased quantum walk as a generator for non-classical position states of the walker. We exploit a phenomenon of coherent localisation in the position space --- resulting from the choice of small values of…

Quantum Physics · Physics 2018-01-09 H. Majury , J. Boutari , E. O'Sullivan , A. Ferraro , M. Paternostro

The classicalization of a decoherent discrete-time quantum walk on a line or an n-cycle can be demonstrated in various ways that do not necessarily provide a geometry-independent description. For example, the position probability…

Quantum Physics · Physics 2010-06-25 R. Srikanth , Subhashish Banerjee , C. M. Chandrashekar

In this paper, we develop a generic controlled alternate quantum walk model (called CQWM-P) by combining parity-dependent quantum walks with distinct arbitrary memory lengths and then construct a quantum-inspired hash function (called…

Quantum Physics · Physics 2023-08-11 Qing Zhou , Xueming Tang , Songfeng Lu , Hao Yang

We implement the discrete-time quantum walk model using the continuous-time evolution of the Hamiltonian that includes both the shift and the coin generators. Based on the Trotter-Suzuki first-order approximation, we consider an…

Quantum Physics · Physics 2022-03-03 Jalil Khatibi Moqadam , Marcos Cesar de Oliveira

Quantum walk models have been used as an algorithmic tool for quantum computation and to describe various physical processes. This paper revisits the relationship between relativistic quantum mechanics and the quantum walks. We show the…

Quantum Physics · Physics 2010-06-29 C. M. Chandrashekar , Subhashish Banerjee , R. Srikanth

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…

We study the dynamics of discrete-time quantum walk using quantum coin operations, $\hat{C}(\theta_1)$ and $\hat{C}(\theta_2)$ in time-dependent periodic sequence. For the two-period quantum walk with the parameters $\theta_1$ and…

Quantum Physics · Physics 2018-01-19 N. Pradeep Kumar , Radhakrishna Balu , Raymond Laflamme , C. M. Chandrashekar

In this paper, a study on discrete-time coined quantum walks on the line is presented. Clear mathematical foundations are still lacking for this quantum walk model. As a step towards this objective, the following question is being…

Quantum Physics · Physics 2013-01-01 Marcos Villagra , Masaki Nakanishi , Shigeru Yamashita , Yasuhiko Nakashima

We establish a necessary and sufficient condition for the existence of a quantum state that reproduces given correlation values in the Clauser--Horne--Shimony--Holt (CHSH) setup for any fixed normalized observables. This result addresses a…

Quantum Physics · Physics 2025-06-17 Ryosuke Nogami , Jaeha Lee

Quantum walks subject to decoherence generically suffer the loss of their genuine quantum feature, a quadratically faster spreading compared to classical random walks. This intuitive statement has been verified analytically for certain…

We show that a quantum state transfer, previously studied as a continuous time process in networks of interacting spins, can be achieved within the model of discrete time quantum walks with position dependent coin. We argue that due to…

Quantum Physics · Physics 2016-10-05 Pawel Kurzynski , Antoni Wojcik

The quantum random walk has been much studied recently, largely due to its highly nonclassical behavior. In this paper, we study one possible route to classical behavior for the discrete quantum walk on the line: the presence of decoherence…

Quantum Physics · Physics 2009-11-07 Todd A. Brun , Hilary A. Carteret , Andris Ambainis

In this paper, we consider discrete time quantum walks on graphs with coin focusing on the decentralized model, where the coin operation is allowed to change with the vertex of the graph. When the coin operations can be modified at every…

Quantum Physics · Physics 2010-06-15 Francesca Albertini , Domenico D'Alessandro

Entanglement is often regarded as an inherently quantum feature. We show that this does not have to be the case: under restricted operational access, classical correlations can appear nonseparable when expressed in the formalism of quantum…

Quantum Physics · Physics 2025-12-18 Samuel Schlegel , Borivoje Dakić , Flavio Del Santo

We introduce a variation of the discrete time quantum walk, the nonreversal quantum walk, which does not step back onto a position which it has just occupied. This allows us to simulate a dimer and we achieve it by introducing a new type of…

Quantum Physics · Physics 2014-06-27 T. J. Proctor , K. E. Barr , B. Hanson , S. Martiel , V. Pavlovic , A. Bullivant , V. M. Kendon

We set the criteria under which superposition of causal order can be incorporated in to quantum walks. In particular, we show that only periodic quantum walks or those with at least one disorder exhibit Superposition of causal order under…

Quantum Physics · Physics 2025-03-11 Prateek Chawla , Shrikant Utagi , C. M. Chandrashekar

We consider to what extent quantum walks can constitute models of thermalization, analogously to how classical random walks can be models for classical thermalization. In a quantum walk over a graph, a walker moves in a superposition of…

Quantum Physics · Physics 2024-06-03 Shyam Dhamapurkar , Oscar Dahlsten

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

Quantum state preparation in high-dimensional systems is an essential requirement for many quantum-technology applications. The engineering of an arbitrary quantum state is, however, typically strongly dependent on the experimental platform…

The aim of this paper is to build quantum circuits that implement discrete-time quantum walks having an arbitrary position-dependent coin operator. The position of the walker is encoded in base 2: with $n$ wires, each corresponding to one…