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Related papers: On nonlinear scattering for quantum walks

200 papers

In this paper, we consider the continuous limit of a nonlinear quantum walk (NLQW) that incorporates a linear quantum walk as a special case. In particular, we rigorously prove that the walker (solution) of the NLQW on a lattice $\delta…

Mathematical Physics · Physics 2020-05-20 Masaya Maeda , Akito Suzuki

We consider the effect of different unitary noise mechanisms on the evolution of a quantum walk (QW) on a linear chain with a generic coin operation: (i) bit-flip channel noise, restricted to the coin subspace of the QW, and (ii)…

Quantum Physics · Physics 2007-11-27 G. Abal , R. Donangelo , F. Severo , R. Siri

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

We examine the physical implementation of a discrete time quantum walk with a four-dimensional coin. Our quantum walker is a photon moving repeatedly through a time delay loop, with time being our position space. The quantum coin is…

Quantum Physics · Physics 2011-03-02 Craig S Hamilton , Aurel Gabris , Igor Jex , Stephen M Barnett

Although quantum walks exhibit peculiar properties that distinguish them from random walks, classical behavior can be recovered in the asymptotic limit by destroying the coherence of the pure state associated to the quantum system. Here I…

Quantum Physics · Physics 2016-06-16 Miquel Montero

The analysis of logarithmic return distributions defined over large time scales is crucial for understanding the long-term dynamics of asset price movements. For large time scales of the order of two trading years, the anticipated Gaussian…

Statistical Finance · Quantitative Finance 2026-04-16 Stijn De Backer , Luis E. C. Rocha , Jan Ryckebusch , Koen Schoors

We consider discrete-time nearest-neighbor quantum walks on random environments in one dimension. Using the method based on a path counting, we present both quenched and annealed weak limit theorems for the quantum walk.

Quantum Physics · Physics 2010-05-12 Norio Konno

We present an in-depth analytic study of discrete-time quantum walks driven by a non-reflective coin. Specifically, we compare the properties of the widely-used Grover coin ${\cal C}_{G}$ that is unitary and reflective (${\cal…

Quantum Physics · Physics 2018-03-22 Stefan Boettcher , Joshua L. Pughe-Sanford

We show that Wronskians between properly chosen linearly independent solutions of the Schr\"odinger equation greatly facilitate the study of quantum scattering in one dimension. They enable one to obtain the necessary relationships between…

Quantum Physics · Physics 2015-03-17 Francisco M. Fernández

A non-unitary version of quantum scattering is studied via an exactly solvable toy model. The model is merely asymptotically local since the smooth path of the coordinate is admitted complex in the non-asymptotic domain. At any real…

Mathematical Physics · Physics 2012-05-21 Miloslav Znojil

A discrete-time Quantum Walk (QW) is an operator driving the evolution of a single particle on the lattice, through local unitaries. Some QW admit, as their continuum limit, a well-known equation of Physics. In arXiv:1803.01015 the QW is…

Quantum Physics · Physics 2018-12-07 Pablo Arrighi , Giuseppe Di Molfetta , Iván Márquez-Martín , Armando Pérez

Motivated by the immense success of random walk and Markov chain methods in the design of classical algorithms, we consider_quantum_ walks on graphs. We analyse in detail the behaviour of unbiased quantum walk on the line, with the example…

Quantum Physics · Physics 2007-05-23 Ashwin Nayak , Ashvin Vishwanath

One-parameter family of discrete-time quantum-walk models on the square lattice, which includes the Grover-walk model as a special case, is analytically studied. Convergence in the long-time limit $t \to \infty$ of all joint moments of two…

Quantum Physics · Physics 2008-06-20 Kyohei Watabe , Naoki Kobayashi , Makoto Katori , Norio Konno

In the literature, there are numerous studies of one-dimensional discrete-time quantum walks (DTQWs) using a moving shift operator. However, there is no exact solution for the limiting probability distributions of DTQWs on cycles using a…

Quantum Physics · Physics 2016-10-20 Xin-Ping Xu , Yusuke Ide

Discrete time (coined) quantum walks are produced by the repeated application of a constant unitary transformation to a quantum system. By recasting these walks into the setting of periodic perturbations to an otherwise freely evolving…

Quantum Physics · Physics 2007-05-23 O. Buerschaper , K. Burnett

Quantum walk acts obviously different from its classical counterpart, but decoherence will lessen and close the gap between them. To understand this process, it is necessary to investigate the evolution of quantum walk under different…

Quantum Physics · Physics 2015-06-04 Peng Xue , Yongsheng Zhang

There are presently two models for quantum walks on graphs. The "coined" walk uses discrete time steps, and contains, besides the particle making the walk, a second quantum system, the coin, that determines the direction in which the…

Quantum Physics · Physics 2009-11-10 Mark Hillery , Janos Bergou , Edgar Feldman

We investigate reflected random walks in the quarter plane, with particular emphasis on the time spent along the reflection boundary axes. Assuming the drift of the random walk lies within the cone, the local time converges -- without the…

Probability · Mathematics 2025-07-08 Viet Hung Hoang , Kilian Raschel

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

In this paper, we present a detailed study on discrete-time Dirac quantum walks (DQWs) on triangular and honeycomb lattices. At the continuous limit, these DQWs coincide with the Dirac equation. Their differences in the discrete regime are…

Quantum Physics · Physics 2019-03-27 Gareth Jay , Fabrice Debbasch , Jingbo B. Wang