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Related papers: Instability in the quantum restart problem

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Classical first-passage times under restart are used in a wide variety of models, yet the quantum version of the problem still misses key concepts. We study the quantum hitting time with restart using a monitored quantum walk. The restart…

Statistical Mechanics · Physics 2023-02-15 Ruoyu Yin , Eli Barkai

We investigate a quantum walk on a ring represented by a directed triangle graph with complex edge weights and monitored at a constant rate until the quantum walker is detected. To this end, the first hitting time statistics is recorded…

Quantum Physics · Physics 2024-04-11 Qingyuan Wang , Silin Ren , Ruoyu Yin , Klaus Ziegler , Eli Barkai , Sabine Tornow

We introduce a novel time-energy uncertainty relation within the context of restarts in monitored quantum dynamics. Initially, we investigate the concept of ``first hitting time'' in quantum systems using an IBM quantum computer and a…

Statistical Mechanics · Physics 2025-01-07 Ruoyu Yin , Qingyuan Wang , Sabine Tornow , Eli Barkai

Interplay between quantum interference and classical randomness can enhance performance of various quantum information tasks. In the present paper we analyze recurrence phenomena in the discrete-time quantum stochastic walk on a line, which…

Quantum Physics · Physics 2026-01-28 Martin Stefanak , Vaclav Potocek , Iskender Yalcinkaya , Aurel Gabris , Igor Jex

Even after decades of research the problem of first passage time statistics for quantum dynamics remains a challenging topic of fundamental and practical importance. Using a projective measurement approach, with a sampling time $\tau$, we…

Statistical Mechanics · Physics 2017-04-05 Harel Friedman , David A. Kessler , Eli Barkai

The mean squared displacement has been widely used as the primary metric for comparing quantum and classical random walks, with quantum walks showing quadratic scaling versus linear scaling for classical walks. However, this comparison may…

Quantum Physics · Physics 2026-03-20 Jan Wójcik

Hitting times for discrete quantum walks on graphs give an average time before the walk reaches an ending condition. To be analogous to the hitting time for a classical walk, the quantum hitting time must involve repeated measurements as…

Quantum Physics · Physics 2009-11-11 Hari Krovi , Todd A. Brun

In the classical stochastic resetting problem, a particle, moving according to some stochastic dynamics, undergoes random interruptions that bring it to a selected domain, and then, the process recommences. Hitherto, the resetting mechanism…

Statistical Mechanics · Physics 2020-12-08 Carlos A. Plata , Deepak Gupta , Sandro Azaele

Hitting times are the average time it takes a walk to reach a given final vertex from a given starting vertex. The hitting time for a classical random walk on a connected graph will always be finite. We show that, by contrast, quantum walks…

Quantum Physics · Physics 2009-11-13 Hari Krovi , Todd A. Brun

We analyze a one-dimensional intermittent random walk on an unbounded domain in the presence of stochastic resetting. In this process, the walker alternates between local intensive search, diffusion, and rapid ballistic relocations in which…

Statistical Mechanics · Physics 2024-01-31 Rosa Flaquer-Galmés , Daniel Campos , Vicenç Méndez

The time it takes a random walker in a lattice to reach the origin from another vertex $x$, has infinite mean. If the walker can restart the walk at $x$ at will, then the minimum expected hitting time $T(x,0)$ (minimized over restarting…

Probability · Mathematics 2010-05-25 Svante Janson , Yuval Peres

We define the hitting time for a model of continuous-time open quantum walks in terms of quantum jumps. Our starting point is a master equation in Lindblad form, which can be taken as the quantum analogue of the rate equation for a…

Quantum Physics · Physics 2017-09-26 A. Chia , T. Paterek , L. C. Kwek

A powerful strategy to accelerate quantum-walk-based search algorithms leverages on resetting protocols, where a detector monitors a target site and the evolution of the walker is restarted if no detection occurs within a fixed time…

Quantum Physics · Physics 2025-11-03 Sayan Roy , Shamik Gupta , Giovanna Morigi

We investigate the splitting probability of a monitored continuous-time quantum walk with two targets and show that, in stark contrast to a classical random walk, it exhibits a nonanalytic, phase-transition-like behavior controlled by the…

Statistical Mechanics · Physics 2026-01-23 Prashant Singh , David A. Kessler , Eli Barkai

We study the first hitting time statistics between a one-dimensional run-and-tumble particle and a target site that switches intermittently between visible and invisible phases. The two-state dynamics of the target is independent of the…

Statistical Mechanics · Physics 2021-05-05 Gabriel Mercado-Vásquez , Denis Boyer

We study the first detected recurrence time problem of continuous-time quantum walks on graphs. While previous works have employed projective measurements to determine the first return time, we implement a protocol based on weak…

Quantum Physics · Physics 2025-06-27 Tim Heine , Eli Barkai , Klaus Ziegler , Sabine Tornow

In this paper, we consider a stochastic process that may experience random reset events which relocate the system to its starting position. We focus our attention on a one-dimensional, monotonic continuous-time random walk with a constant…

Mathematical Physics · Physics 2017-10-11 Miquel Montero , Axel Masó-Puigdellosas , Javier Villarroel

We investigate the effects of markovian resseting events on continuous time random walks where the waiting times and the jump lengths are random variables distributed according to power law probability density functions. We prove the…

Statistical Mechanics · Physics 2021-02-10 Vicenç Méndez , Axel Masó-Puigdellosas , Trifce Sandev , Daniel Campos

We predict that continuously monitored quantum dynamics can be chaotic. The optimal paths between past and future boundary conditions can diverge exponentially in time when there is time-dependent evolution and continuous weak monitoring.…

Quantum Physics · Physics 2018-08-08 Philippe Lewalle , John Steinmetz , Andrew N. Jordan

A discrete time quantum walk is considered in which the step lengths are chosen to be either $1$ or $2$ with the additional feature that the walker is persistent with a probability $p$. This implies that with probability $p$, the walker…

Quantum Physics · Physics 2020-04-08 Suchetana Mukhopadhyay , Parongama Sen
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