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Related papers: A study of Wigner functions for discrete-time quan…

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The central aim of the thesis is to examine how non-classical resources in finite-dimensional quantum systems can be identified, characterized, and protected for practical use in the presence of realistic noise. Using the discrete Wigner…

Quantum Physics · Physics 2026-05-29 Jai Lalita

The entanglement between the position and coin state of a $N$-dimensional quantum walker is shown to lead to a thermodynamic theory. The entropy, in this thermodynamics, is associated to the reduced density operator for the evolution of…

Quantum Physics · Physics 2015-06-22 Alejandro Romanelli , Raul Donangelo , Renato Portugal , Franklin L. Marquezino

It is common knowledge that the Wigner function of a quantum state may admit negative values, so that it cannot be viewed as a genuine probability density. Here, we examine the difficulty in finding an entropy-like functional in phase space…

Quantum Physics · Physics 2026-01-27 Nicolas J. Cerf , Anaelle Hertz , Zacharie Van Herstraeten

We derive the continuous spacetime limit of the one dimensional lazy discrete time quantum walk, obtaining explicit macroscopic evolution equations for a three state model in the presence of decoherence. While continuum limits of two state…

Quantum Physics · Physics 2026-01-19 Lara Janiurek , Viv Kendon

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

The manner in which unpredictable chaotic dynamics manifests itself in quantum mechanics is a key question in the field of quantum chaos. Indeed, very distinct quantum features can appear due to underlying classical nonlinear dynamics. Here…

Quantum Physics · Physics 2014-03-07 G. B. Lemos , R. M. Gomes , S. P. Walborn , P. H. Souto Ribeiro , F. Toscano

Discrete quantum walks are periodically driven systems with discrete time evolution. In contrast to ordinary Floquet systems, no microscopic Hamiltonian exists, and the one-period time evolution is given directly by a series of unitary…

Mesoscale and Nanoscale Physics · Physics 2025-01-10 Ken Mochizuki , Takumi Bessho , Masatoshi Sato , Hideaki Obuse

We show that quantum circuits where the initial state and all the following quantum operations can be represented by positive Wigner functions can be classically efficiently simulated. This is true both for continuous-variable as well as…

Quantum Physics · Physics 2015-06-11 A. Mari , J. Eisert

In most widely discussed discrete time quantum walk model, after every unitary shift operator, the particle evolves into the superposition of position space and settles down in one of its basis states, loosing entanglement in the coin space…

Quantum Physics · Physics 2007-05-23 C. M. Chandrashekar

The Wigner function, which provides a phase-space description of quantum systems, has various applications in quantum mechanics, quantum kinetic theory, quantum optics, radiation transport and others. The concept of Wigner function has been…

High Energy Physics - Theory · Physics 2013-04-05 Stanislaw Mrowczynski

In this letter, the number-phase entropic uncertainty relation and the number-phase Wigner function of generalized coherent states associated to a few solvable quantum systems with nondegenerate spectra are studied. We also investigate time…

Quantum Physics · Physics 2009-09-30 G. R. Honarasa , M. K. Tavassoly , M. Hatami

This manuscript gathers and subsumes a long series of works on using QW to simulate transport phenomena. Quantum Walks (QWs) consist of single and isolated quantum systems, evolving in discrete or continuous time steps according to a…

Quantum Physics · Physics 2021-12-23 Giuseppe Di Molfetta

Quantum walks are known to propagate quadratically faster than their classical counterparts and are used to model dynamics in various quantum systems. The spread of the quantum walk in position space shows anomalous diffusion behavior. By…

Quantum Physics · Physics 2022-05-24 Abhaya S. Hegde , C. M. Chandrashekar

We study one-dimensional quantum walk with four internal degrees of freedom resulted from two entangled qubits. We will demonstrate that the entanglement between the qubits and its corresponding coin operator enable one to steer the…

Quantum Physics · Physics 2020-07-01 S. Panahiyan , S. Fritzsche

An observer at rest with the expanding universe experiences some extra noise in the quantum vacuum, and so does an accelerated observer in a vacuum at rest (in Minkowski space). The literature mainly focuses on the ideal cases of…

General Relativity and Quantum Cosmology · Physics 2025-01-07 Ziv Landau , Ulf Leonhardt

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 investigate the global chirality distribution of the quantum walk on the line when decoherence is introduced either through simultaneous measurements of the chirality and particle position, or as a result of broken links. The first…

Quantum Physics · Physics 2015-05-19 Alejandro Romanelli , Guzmán Hernández

We study the Wigner Function in non-commutative quantum mechanics. By solving the time independent Schr\"{o}dinger equation both on a non-commutative (NC) space and a non-commutative phase space, we obtain the Wigner Function for the…

High Energy Physics - Theory · Physics 2009-08-13 Jianhua Wang , Kang Li , Sayipjamal Dulat

The capability to generate and manipulate quantum states in high-dimensional Hilbert spaces is a crucial step for the development of quantum technologies, from quantum communication to quantum computation. One-dimensional quantum walk…

The question of witnessing or quantifying nonclassicality of quantum systems has been addressed in various ways. For a given system or theory, we propose identifying it with the incompatibility of admissible states. We quantify the…

Quantum Physics · Physics 2013-12-05 Pavan Iyengar , G. N. Chandan , R. Srikanth