English
Related papers

Related papers: Euclidean time method in Generalized Eigenvalue Eq…

200 papers

We explore the possibility of modifying the Lewis-Riesenfeld method of invariants developed originally to find exact solutions for time-dependent quantum mechanical systems for the situation in which an exact invariant can be constructed,…

Quantum Physics · Physics 2020-02-03 Andreas Fring , Rebecca Tenney

We obtain the quantized momentum eigenvalues, $P_n$ , and the momentum eigenstates for the space-like Schr\"odinger equation, the Feinberg-Horodecki equation, with the general potential which is constructed by the temporal counterpart of…

Quantum Physics · Physics 2020-07-29 Mahmoud Farout , Ahmed Bassalat , Sameer M. Ikhdair

We introduce a new discrete-time variational principle inspired by the quantum clock originally proposed by Feynman, and use it to write down quantum evolution as a ground state eigenvalue problem. The construction allows one to apply…

Quantum Physics · Physics 2014-03-05 Jarrod R. McClean , John A. Parkhill , Alán Aspuru-Guzik

We present an efficient method for preparing the initial state required by the eigenvalue approximation quantum algorithm of Abrams and Lloyd. Our method can be applied when solving continuous Hermitian eigenproblems, e.g., the Schroedinger…

Quantum Physics · Physics 2009-11-10 Peter Jaksch , Anargyros Papageorgiou

The variational quantum eigensolver (VQE) is a method that uses a hybrid quantum-classical computational approach to find eigenvalues and eigenvalues of a Hamiltonian. VQE has been proposed as an alternative to fully quantum algorithms such…

Quantum Physics · Physics 2021-09-01 Dmitry A. Fedorov , Bo Peng , Niranjan Govind , Yuri Alexeev

Path integrals are usually formulated in discrete Euclidean time using the Trotter formula. We propose a new method to study discrete quantum systems, in which we work directly in the Euclidean time continuum. The method is of general…

Condensed Matter · Physics 2014-10-13 B. B. Beard , U. -J. Wiese

We extend our finite difference time domain method for numerical solution of the Schrodinger equation to cases where eigenfunctions are complex-valued. Illustrative numerical results for an electron in two dimensions, subject to a confining…

Computational Physics · Physics 2008-07-05 I. Wayan Sudiarta , D. J. Wallace Geldart

We generalize the Lewis-Riesenfeld technique of solving the time-dependent Schrodinger equation to cases where the invariant has continuous eigenvalues. An explicit formula for a generalized Lewis-Riesenfeld phase is derived in terms of the…

Quantum Physics · Physics 2008-04-29 M. Maamache , Y. Saadi

We argue that the way to get the general solution of a Schrodinger equation in the presence of a time-dependent linear potential based on the Lewis-Riesenfeld framework is to use a Hermitian linear invariant operator. We demonstrate that…

Quantum Physics · Physics 2008-05-06 M. Maamache , Y. Saadi

An algorithm for the numerical solution of the Schr\"odinger equation in the case of a time dependent potential is proposed. Our simple modification upgrades the well known method of Koonin while negligibly increasing the computing time. In…

Nuclear Theory · Physics 2009-10-28 R. Schaefer , R. Blendowske

For a large class of time-dependent non-Hermitain Hamiltonians expressed in terms linear and bilinear combinations of the generators for an Euclidean Lie-algebra respecting different types of PT-symmetries, we find explicit solutions to the…

Quantum Physics · Physics 2019-01-17 Andreas Fring , Thomas Frith

An algorithm named EigenWave is described to compute eigenvalues and eigenvectors of elliptic boundary value problems. The algorithm, based on the recently developed WaveHoltz scheme, solves a related time-dependent wave equation as part of…

Numerical Analysis · Mathematics 2025-07-25 Daniel Appelo , Jeffrey W. Banks , William D. Henshaw , Ngan Le , Donald W. Schwendeman

For quantum mechanics of a charged particle in a classical external electromagnetic field, there is an apparent puzzle that the matrix element of the canonical momentum and Hamiltonian operators is gauge dependent. A resolution to this…

High Energy Physics - Phenomenology · Physics 2015-05-18 Wei-Min Sun , Xiang-Song Chen , Xiao-Fu Lu , Fan Wang

In this paper, we present a direct quantum adaptation of the classical shifted power method. The method is very similar to the iterative phase estimation algorithm; however, it does not require any initial estimate of an eigenvector and as…

Quantum Physics · Physics 2023-01-13 Ammar Daskin

In a previous paper (J. Phys. A 36, 11807 (2003)), we introduced the `asymptotic iteration method' for solving second-order homogeneous linear differential equations. In this paper, we study perturbed problems in quantum mechanics and we…

Mathematical Physics · Physics 2009-11-11 Hakan Ciftci , Richard L. Hall , Nasser Saad

We develop a quantum filter diagonalization method (QFD) that lies somewhere between the variational quantum eigensolver (VQE) and the phase estimation algorithm (PEA) in terms of required quantum circuit resources and conceptual…

Quantum Physics · Physics 2019-09-20 Robert M. Parrish , Peter L. McMahon

A variational technique is established to deal with the Schrodinger equation with parity-time(PT) symmetric Gaussian complex potential. The method is extended to the linear and self-focusing and defocusing nonlinear cases. Some unusual…

Pattern Formation and Solitons · Physics 2012-03-09 Sumei Hu , Guo Liang , Shanyong Cai , Daquan Lu , Qi Guo , Wei Hu

We have developed a variational perturbation theory based on the Liouville-Neumann equation, which enables one to systematically compute the perturbative correction terms to the variationally determined wave functions of the time-dependent…

High Energy Physics - Theory · Physics 2008-11-26 Dongsu Bak , Sang Pyo Kim , Sung Ku Kim , Kwang-Sup Soh , Jae Hyung Yee

We present a simple algebraic procedure that can be applied to solve a range of quantum eigenvalue problems without the need to know the solution of the Schr\"odinger equation. The procedure, presented with a pedagogical purpose, is based…

Quantum Physics · Physics 2021-11-17 Luis de la Peña , Ana María Cetto , Andrea Valdés-Hernández

Existing approaches to analogue quantum simulations of time-dependent quantum systems rely on perturbative corrections to quantum simulations of time-independent quantum systems. We overcome this restriction to perturbative treatments with…

Quantum Physics · Physics 2024-02-13 Boyuan Shi , Florian Mintert