English
Related papers

Related papers: Quantum Phase Operator and Phase States

200 papers

We present efficient implementations of a number of operations for quantum computers. These include controlled phase adjustments of the amplitudes in a superposition, permutations, approximations of transformations and generalizations of…

Quantum Physics · Physics 2014-11-18 Tad Hogg , Carlos Mochon , Wolfgang Polak , Eleanor Rieffel

We analyze the behavior of a quantum system described by a one-dimensional asymmetric potential consisting of a step plus a harmonic barrier. We solve the eigenvalue equation by the integral representation method, which allows us to…

Quantum Physics · Physics 2010-07-16 Luca Rizzi , Oliver F. Piattella , Sergio L. Cacciatori , Vittorio Gorini

Quantum computing has been increasingly applied in nuclear physics. In this work, we combine quantum computing with the complex scaling method to address the resonance problem. Due to the non-Hermiticity introduced by complex scaling,…

Nuclear Theory · Physics 2024-09-11 Hantao Zhang , Dong Bai , Zhongzhou Ren

The Wigner-Weyl transform and phase space formulation of a density matrix approach are applied to a non-Hermitian model which is quadratic in positions and momenta. We show that in the presence of a quantum environment or reservoir, mean…

Quantum Physics · Physics 2019-10-09 Ludmila Praxmeyer , Konstantin G. Zloshchastiev

Quantum tomography can reconstruct fine phase-space structures that are not necessarily resolved by measurement itself. We show that the effective resolution of tomography is determined by a sampling operator linked to the Gram matrix of…

Quantum Physics · Physics 2026-05-29 Zdenek Hradil , Jaroslav Rehacek

Quantum signal processing (QSP) provides a representation of scalar polynomials of degree $d$ as products of matrices in $\mathrm{SU}(2)$, parameterized by $(d+1)$ real numbers known as phase factors. QSP is the mathematical foundation of…

Quantum Physics · Physics 2025-10-02 Lin Lin

We propose a time-of-arrival operator in quantum mechanics by conditioning on a quantum clock. This allows us to bypass some of the problems of previous proposals, and to obtain a Hermitian time of arrival operator whose probability…

Quantum Physics · Physics 2020-03-19 Lorenzo Maccone , Krzysztof Sacha

The relation that exists in quantum mechanics among action variables, angle variables and the phases of quantum states is clarified, by referring to the system of a generalized oscillator. As a by-product, quantum-mechanical meaning of the…

High Energy Physics - Theory · Physics 2007-05-23 M. Omote , S. Sakoda , S. Kamefuchi

We present efficient circuits that can be used for the phase space tomography of quantum states. The circuits evaluate individual values or selected averages of the Wigner, Kirkwood and Husimi distributions. These quantum gate arrays can be…

Quantum Physics · Physics 2009-11-10 Juan Pablo Paz , Augusto J. Roncaglia , Marcos Saraceno

A time operator is a Hermitian operator that is canonically conjugate to a given Hamiltonian. For a particle in 1-dimension, a Hamiltonian conjugate operator in position representation can be obtained by solving a hyperbolic second-order…

Quantum Physics · Physics 2024-09-06 Ralph Adrian E. Farrales , Herbert B. Domingo , Eric A. Galapon

Geometric phases arise naturally in a variety of quantum systems with observable consequences. They also arise in quantum computations when dressed states are used in gating operations. Here we show how they arise in these gating operations…

Quantum Physics · Physics 2013-05-29 Lian-Ao Wu , C. Allen Bishop , Mark S. Byrd

Implementing general functions of operators is a powerful tool in quantum computation. It can be used as the basis for a variety of quantum algorithms including matrix inversion, real and imaginary-time evolution, and matrix powers. Quantum…

Quantum Physics · Physics 2022-06-08 Thais de Lima Silva , Lucas Borges , Leandro Aolita

We revisit the topic of two-state quantum systems using Geometric Algebra (GA) in three dimensions $\mathcal G_3$. In this description, both the quantum states and Hermitian operators are written as elements of $\mathcal G_3$. By writing…

Mathematical Physics · Physics 2021-03-10 Pedro Amao , Hernán Castillo

A general procedure for constructing coherent states, which are eigenstates of annihilation operators, related to quantum mechanical potential problems, is presented. These coherent states, by construction are not potential specific and…

Quantum Physics · Physics 2007-05-23 P. K. Panigrahi , T. Shreecharan , J. Banerji , V. Sundaram

Quantum Signal Processing (QSP) is a technique that can be used to implement a polynomial transformation $P(x)$ applied to the eigenvalues of a unitary $U$, essentially implementing the operation $P(U)$, provided that $P$ satisfies some…

Quantum Physics · Physics 2023-03-21 Lorenzo Laneve

A self-adjoint operator with dimensions of time is explicitly constructed, and it is shown that its complete and orthonormal set of eigenstates can be used to define consistently a probability distribution of the time of arrival at a…

Quantum Physics · Physics 2008-02-03 V. Delgado , J. G. Muga

Coherent states, and the Hilbert space representations they generate, provide ideal tools to discuss classical/quantum relationships. In this paper we analyze three separate classical/quantum problems using coherent states, and show that…

Quantum Physics · Physics 2015-05-19 John R. Klauder

This paper is dedicated to finding the quadrature operator eigenstates and wavefunctions of the most general $f$-deformed oscillators. A definition for quadrature operator for deformed algebra is derived to obtain the quadrature operator…

Quantum Physics · Physics 2021-05-07 S. Anupama , Aditi Pradeep , Adipta Pal , C. Sudheesh

This paper is concerned with the construction of phase operators, phase states, vector phase states, and coherent states for a generalized Weyl-Heisenberg algebra. This polynomial algebra (that depends on real parameters) is briefly…

Quantum Physics · Physics 2012-10-17 Maurice Robert Kibler , Mohammed Daoud

Finite frame quantization is a discrete version of the coherent state quantization. In the case of a quantum system with finite-dimensional Hilbert space, the finite frame quantization allows us to associate a linear operator to each…

Quantum Physics · Physics 2022-07-18 Nicolae Cotfas