English
Related papers

Related papers: Quantum Magic in Discrete-Time Quantum Walk

200 papers

Consumption of magic states promotes the stabilizer model of computation to universal quantum computation. Here, we propose three different classical algorithms for simulating such universal quantum circuits, and characterize them by…

Quantum Physics · Physics 2021-03-23 James R. Seddon , Bartosz Regula , Hakop Pashayan , Yingkai Ouyang , Earl T. Campbell

Entanglement generation in discrete time quantum walks is deemed to be another key property beyond the transport behaviors. The latter has been widely used in investigating the localization or topology in quantum walks. However, there are…

In this article we investigate the effects of shifting position decoherence, arisen from the tunneling effect in the experimental realization of the quantum walk, on the one-dimensional discreet time quantum walk. We show that in the regime…

Quantum Physics · Physics 2017-06-06 Mostafa Annabestani , Seyed Javad Akhtarshenas , Mohamad Reza Abolhassani

Quantum walks have proven to be a universal model for quantum computation and to provide speed-up in certain quantum algorithms. The discrete-time quantum walk (DTQW) model, among others, is one of the most suitable candidates for circuit…

Quantum Physics · Physics 2024-04-10 Luca Razzoli , Gabriele Cenedese , Maria Bondani , Giuliano Benenti

Coined quantum walks may be interpreted as the motion in position space of a quantum particle with a spin degree of freedom; the dynamics are determined by iterating a unitary transformation which is the product of a spin transformation and…

Quantum Physics · Physics 2007-05-23 Alex D. Gottlieb , Svante Janson , Petra F. Scudo

Quantum Key Distribution (QKD) is an emerging cryptographic method designed for secure key sharing. Its security is theoretically guaranteed by fundamental principles of quantum mechanics, making it a leading candidate for future…

Quantum Physics · Physics 2025-12-03 Chia-Tso Lai

Quantum random walks are the quantum counterpart of classical random walks, and were recently studied in the context of quantum computation. A quantum random walker is subject to self interference, leading to a remarkably different behavior…

Nonstabilizerness, or quantum magic, presents a valuable resource in quantum error correction and computation. We study the dynamics of locally injected magic in unitary Clifford circuits, where the total magic is conserved. However, the…

Quantum Physics · Physics 2025-11-27 Mircea Bejan , Pieter W. Claeys , Jiangtian Yao

We study the dynamical localization of discrete time evolution of topological split-step quantum random walk (QRW) on a single-site defect starting from a uniform distribution. Using analytical and numerical calculations, we determine the…

Quantum Physics · Physics 2025-02-14 D. O. Oriekhov , Guliuxin Jin , Eliska Greplova

We introduce a novel measure for the quantum property of nonstabilizerness - commonly known as "magic" - by considering the R\'enyi entropy of the probability distribution associated to a pure quantum state given by the square of the…

Quantum Physics · Physics 2022-03-15 Lorenzo Leone , Salvatore F. E. Oliviero , Alioscia Hamma

In quantum computing, the nonstabilizerness of quantum operations is crucial for understanding and quantifying quantum speedups. In this study, we explore the phenomena of nonstabilizerness of the quantum SWITCH, a novel structure that…

Quantum Physics · Physics 2024-07-31 Yin Mo , Chengkai Zhu , Zhiping Liu , Mingrui Jing , Xin Wang

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

Consider a discrete-time quantum walk on the $N$-cycle subject to decoherence both on the coin and the position degrees of freedom. By examining the evolution of the density matrix of the system, we derive some new conclusions about the…

Quantum Physics · Physics 2011-07-20 Chaobin Liu , Nelson Petulante

The discrete-time quantum walk is a quantum counterpart of the random walk. It is expected that the model plays important roles in the quantum field. In the quantum information theory, entanglement is a key resource. We use the von Neumann…

Quantum Physics · Physics 2011-09-21 Yusuke Ide , Norio Konno , Takuya Machida

A quantum walk places a traverser into a superposition of both graph location and traversal "spin." The walk is defined by an initial condition, an evolution determined by a unitary coin/shift-operator, and a measurement based on the…

Quantum Physics · Physics 2015-11-25 Marko A. Rodriguez , Jennifer H. Watkins

We study a quantum walker on a one-dimensional lattice with a single defect site characterized by a phase. The spread and localization of discrete-time quantum walks starting at the impurity site are affected by the appearance of bound…

Quantum Physics · Physics 2019-05-10 B. Danacı , G. Karpat , İ. Yalçınkaya , A. L. Subaşı

We report on the possibility of controlling quantum random walks with a step-dependent coin. The coin is characterized by a (single) rotation angle. Considering different rotation angles, one can find diverse probability distributions for…

Quantum Physics · Physics 2018-08-23 S. Panahiyan , S. Fritzsche

Quantum walks (QWs) exhibit different properties compared with classical random walks (RWs), most notably by linear spreading and localization. In the meantime, random walks that replicate quantum walks, which we refer to as…

Mathematical Physics · Physics 2022-11-01 Tomoki Yamagami , Etsuo Segawa , Nicolas Chauvet , André Röhm , Ryoichi Horisaki , Makoto Naruse

In this paper, we investigate the enhancement of delocalization and coin-position entanglement in asymmetric discrete-time quantum walks (DTQWs). The asymmetry results from asymmetric coin operations, asymmetric initial states, and…

In this paper, the 2-state decomposed-type quantum walk (DQW) on a line is introduced as an extension of the 2-state quantum walk (QW). The time evolution of the DQW is defined with two different matrices, one is assigned to a real…

Mathematical Physics · Physics 2021-10-11 Chusei Kiumi