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We consider the discrete time unitary dynamics given by a quantum walk on the lattice $\Z^d$ performed by a quantum particle with internal degree of freedom, called coin state, according to the following iterated rule: a unitary update of…

Mathematical Physics · Physics 2015-05-20 Alain Joye

Discrete-time quantum walks (DTQWs) in random artificial electric and gravitational fields are studied analytically and numerically. The analytical computations are carried by a new method which allows a direct exact analytical…

Quantum Physics · Physics 2017-04-25 G. Di Molfetta , F. Debbasch

Differential dynamic microscopy (DDM) is a form of video image analysis that combines the sensitivity of scattering and the direct visualization benefits of microscopy. DDM is broadly useful in determining dynamical properties including the…

Soft Condensed Matter · Physics 2022-04-12 Mengyang Gu , Yimin Luo , Yue He , Matthew E. Helgeson , Megan T. Valentine

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

We discuss the model of a one-dimensional, discrete-time walk on a line with spatial heterogeneity in the form of a variable set of ultrametric barriers. Inspired by the homogeneous quantum walk on a line, we develop a formalism by which…

Quantum Physics · Physics 2020-07-08 Stefan Boettcher

Basic ideas and results which characterize quantum diffusion of defects in quantum crystals like solid helium as a new phenomenon are presented. Quantum effects in such media lead to a delocalization of point defects (vacancies, impurities…

Materials Science · Physics 2009-11-10 Dimitar I. Pushkarov

Quantum walks on graphs can model physical processes and serve as efficient tools in quantum information theory. Once we admit random variations in the connectivity of the underlying graph, we arrive at the problem of percolation, where the…

Quantum Physics · Physics 2014-02-12 Bálint Kollár , Jaroslav Novotný , Tamás Kiss , Igor Jex

We investigate the evolution dynamics of inhomogeneous discrete-time one-dimensional quantum walks displaying long-range correlations in both space and time. The associated quantum coin operators are built to exhibit a random inhomogeneity…

Quantum Physics · Physics 2023-07-12 A. R. C. Buarque , F. S. Passos , W. S. Dias , E. P. Raposo

This study investigates quantum-enhanced parameter estimation through continuous monitoring in open quantum systems that exhibit a dissipative time crystal phase. We first analytically derive the global quantum Fisher information (QFI) rate…

We use discrete-event simulation on a digital computer to study two different models of experimentally realizable quantum walks. The simulation models comply with Einstein locality, are as "realistic" as the one of the simple random walk in…

Quantum Physics · Physics 2020-05-08 Madita Willsch , Dennis Willsch , Kristel Michielsen , Hans De Raedt

The diffraction pattern of a single non-periodic compact object, such as a molecule, is continuous and is proportional to the square modulus of the Fourier transform of that object. When arrayed in a crystal, the coherent sum of the…

We propose a method for temperature measurement by analyzing the frequency of generated time crystals in one-dimensional (1D) quantum droplets. The system consists of a binary Bose-Einstein condensate mixture confined in a driven…

Quantum Gases · Physics 2025-08-07 Saurab Das , Jagnyaseni Jogania , Jayanta Bera , Ajay Nath

Previous experimental realizations of Dicke model in atomic or ionic systems are based on global observables assuming uniform spin-boson coupling, while inevitable experimental nonuniformity on the one hand requires site-resolved…

This thesis develops a general theoretical and numerical framework for achieving high-contrast atom interferometry based on double Bragg diffraction (DBD). While DBD offers intrinsic symmetry, reduced sensitivity to internal-state…

Quantum Physics · Physics 2026-03-25 Rui Li

A discrete-time quantum walk is the quantum analogue of a Markov chain on a graph. Zhan [J. Algebraic Combin. 53(4):1187-1213, 2020] proposes a model of discrete-time quantum walk whose transition matrix is given by two reflections, using…

Combinatorics · Mathematics 2022-11-24 Krystal Guo , Vincent Schmeits

We present an experimental implementation of the coined discrete time quantum walk on a square using a three qubit liquid state nuclear magnetic resonance (NMR) quantum information processor (QIP). Contrary to its classical counterpart, we…

Quantum Physics · Physics 2009-11-11 C. A. Ryan , M. Laforest , J. C. Boileau , R. Laflamme

The role of classical noise in quantum walks (QW) on integers is investigated in the form of discrete dichotomic random variable affecting its reshuffling matrix parametrized as a SU2)/U(1) coset element. Analysis in terms of quantum…

Quantum Physics · Physics 2015-06-05 D. Ellinas , A. J. Bracken , I. Smyrnakis

Decoded Quantum Interferometry (DQI) is a recently proposed quantum optimization algorithm that exploits sparsity in the Fourier spectrum of objective functions, with the potential for exponential speedups over classical algorithms on…

Quantum Physics · Physics 2026-03-09 Kaifeng Bu , Weichen Gu , Dax Enshan Koh , Xiang Li

We develop a theory for the trajectory of an x ray in the presence of a crystal deformation. A set of equations of motion for an x-ray wave packet including the dynamical diffraction is derived, taking into account the Berry phase as a…

Materials Science · Physics 2007-05-23 Kei Sawada , Shuichi Murakami , Naoto Nagaosa

We present a new variational model for computing the electronic first-order density matrix of a crystalline material in presence of a local defect. A natural way to obtain variational discretizations of this model is to expand the…

Other Condensed Matter · Physics 2009-11-13 Eric Cances , Amelie Deleurence , Mathieu Lewin