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Related papers: Quantum walk as a generalized measuring device

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In this paper, we present a quantum Bernoulli noises approach to quantum walks on hypercubes. We first obtain an alternative description of a general hypercube and then, based on the alternative description, we find that the operators…

Quantum Physics · Physics 2022-11-24 Ce Wang

In accordance with the fact that quantum measurements are described in terms of positive operator measures (POMs), we consider certain aspects of a quantization scheme in which a classical variable $f:\R^2\to \R$ is associated with a unique…

Quantum Physics · Physics 2015-06-26 J. Kiukas , P. Lahti

We address the performance of a coin-biased quantum walk as a generator for non-classical position states of the walker. We exploit a phenomenon of coherent localisation in the position space --- resulting from the choice of small values of…

Quantum Physics · Physics 2018-01-09 H. Majury , J. Boutari , E. O'Sullivan , A. Ferraro , M. Paternostro

We present adaptive measurement techniques tailored for variational quantum algorithms on near-term small and noisy devices. In particular, we generalise earlier "learning to measure" strategies in two ways. First, by considering a class of…

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

Complete measurement of a quantum observable (POVM) is a measurement of the maximally refined version of the POVM. Complete measurements give information on multiplicities of measurement outcomes and can be viewed as state preparation…

Quantum Physics · Physics 2015-06-05 Juha-Pekka Pellonpää

For quantum computation using photons, performing deterministic quantum gate operations is a challenge due to the probabilistic nature of the photon-photon interaction. Encoding qubits in multiple degrees-of-freedom of photons and…

Quantum Physics · Physics 2025-08-28 Kanad Sengupta , S. P. Dinesh , K. Muhammed Shafi , Soumya Asokan , C. M. Chandrashekar

Quantum walks have emerged as an interesting approach to quantum information processing, exhibiting many unique properties compared to the analogous classical random walk. Here we introduce a model for a discrete-time quantum walk with…

Quantum Physics · Physics 2013-05-08 Peter P. Rohde , Gavin K. Brennen , Alexei Gilchrist

We consider a new model of quantum walk on a one-dimensional momentum space that includes both discrete jumps and continuous drift. Its time evolution has two stages; a Markov diffusion followed by localized dynamics. As in the well known…

Quantum Physics · Physics 2009-11-10 A. Romanelli , A. Auyuanet , R. Siri , G. Abal , R. Donangelo

Quantum walks are more than tools for building quantum algorithms. They have been used effectively to model and simulate quantum dynamics in many complex physical processes. Particularly, a variant of discrete-time quantum walk known as…

Quantum Physics · Physics 2023-01-05 P. A. Ameen Yasir , Abhaya S. Hegde , C. M. Chandrashekar

A quantum walk is a time-homogeneous quantum-mechanical process on a graph defined by analogy to classical random walk. The quantum walker is a particle that moves from a given vertex to adjacent vertices in quantum superposition. Here we…

Quantum Physics · Physics 2013-02-18 Andrew M. Childs , David Gosset , Zak Webb

Measurements play an important role in quantum computing (QC), by either providing the nonlinearity required for two-qubit gates (linear optics QC), or by implementing a quantum algorithm using single-qubit measurements on a highly…

Quantum Physics · Physics 2008-11-17 Radu Ionicioiu , Anca E. Popescu , William J. Munro , Timothy P. Spiller

We construct the set of all general (i.e. not necessarily rank 1) symmetric informationally complete (SIC) positive operator valued measures (POVMs). In particular, we show that any orthonormal basis of a real vector space of dimension…

Quantum Physics · Physics 2014-08-15 Amir Kalev , Gilad Gour

We propose a novel implementation of discrete time quantum walks for a neutral atom in an array of optical microtraps or an optical lattice. We analyze a one-dimensional walk in position space, with the coin, the additional qubit degree of…

Quantum Physics · Physics 2009-11-11 K. Eckert , J. Mompart , G. Birkl , M. Lewenstein

Device-independent (DI) quantum protocols exploit Bell inequality violations to ensure security or certify quantum properties without making assumptions about the internal workings of the devices. In this work, we study the role of rank-one…

Quantum walks with one-dimensional translational symmetry are important for quantum algorithms, where the speed-up of the diffusion speed can be reached if long-range couplings are added. Our work studies a scheme of a ring under the strong…

Quantum Physics · Physics 2026-02-17 Yixiang Zhang , Xin Qiao , Luojia Wang , Yanyan He , Zhaohui Dong , Xianfeng Chen , Luqi Yuan

For a quantum measurement process described by a quantum instrument $\mathcal{I}$ and a system observable corresponding to a positive-operator valued measure (POVM) $E ,$ $\mathcal{I}$ is said to conserve the information of $E$ if the joint…

Quantum Physics · Physics 2015-09-30 Yui Kuramochi

In a previous paper we have presented a general scheme for the implementation of symmetric generalized measurements (POVMs) on a quantum computer. This scheme is based on representation theory of groups and methods to decompose matrices…

Quantum Physics · Physics 2015-06-26 Dominik Janzing , Thomas Decker

We solve an open problem by constructing quantum walks that not only detect but also find marked vertices in a graph. In the case when the marked set $M$ consists of a single vertex, the number of steps of the quantum walk is quadratically…

Quantum Physics · Physics 2016-03-01 Hari Krovi , Frédéric Magniez , Maris Ozols , Jérémie Roland

We consider the two-state space-inhomogeneous coined quantum walk (QW) in one dimension. For a general setting, we obtain the stationary measure of the QW by solving the eigenvalue problem. As a corollary, stationary measures of the…

Quantum Physics · Physics 2018-08-24 Hikari Kawai , Takashi Komatsu , Norio Konno