English
Related papers

Related papers: Effective Hamiltonians for Constrained Quantum Sys…

200 papers

We propose a simple quantum algorithm for simulating highly oscillatory quantum dynamics, which does not require complicated quantum control logic for handling time-ordering operators. To our knowledge, this is the first quantum algorithm…

Quantum Physics · Physics 2022-04-20 Dong An , Di Fang , Lin Lin

Effective Hamiltonians governing the time evolution in a subspace of unstable states can be found using more or less accurate approximations. A convenient tool for deriving them is the evolution equation for a subspace of state space…

Quantum Physics · Physics 2014-09-11 K. Urbanowski

A new quantum model with rational functions for the potential and effective mass is proposed in a stretchable region outside which both are constant. Starting from a generalized effective mass kinetic energy operator the matching and…

Quantum Physics · Physics 2009-11-13 A. Ganguly , M. V. Ioffe , L. M. Nieto

We consider the inverse problem of H\"oldder-stably determining the time- and space-dependent coefficients of the Schr\"odinger equation on a simple Riemannian manifold with boundary of dimension $n\geq2$ from knowledge of the…

Analysis of PDEs · Mathematics 2019-01-29 Yavar Kian , Alexander Tetlow

We consider a nonlinear Schr\"odinger equation with a bounded local potential in $R^3$. The linear Hamiltonian is assumed to have two bound states with the eigenvalues satisfying some resonance condition. Suppose that the initial data are…

Mathematical Physics · Physics 2007-05-23 Tai-Peng Tsai , Horng-Tzer Yau

We derive one-dimensional effective Hamiltonians for spin-orbit coupled Fermi gases confined in quasi-one-dimensional trapping potentials. For energy regime around the two-body bound state energy, the effective Hamiltonian takes a…

Quantum Gases · Physics 2013-11-13 Ren Zhang , Wei Zhang

We study the valence electron of an alkaline atom or a general charged particle with arbitrary spin and with magnetic moment moving in a rotating magnetic field. By using a time-dependent unitary transformation, the Schr\"odinger equation…

Quantum Physics · Physics 2009-11-07 Qiong-gui Lin

There exist a number of typical and interesting systems or models which possess three-generator Lie-algebraic structure in atomic physics, quantum optics, nuclear physics and laser physics. The well-known fact that all simple 3-generator…

Quantum Physics · Physics 2007-05-23 Jian-Qi Shen , Hong-Yi Zhu , Pan Chen

When numerically simulating the unitary time evolution of an infinite-dimensional quantum system, one is usually led to treat the Hamiltonian $H$ as an "infinite-dimensional matrix" by expressing it in some orthonormal basis of the Hilbert…

Quantum Physics · Physics 2026-01-28 Felix Fischer , Daniel Burgarth , Davide Lonigro

We consider quantum systems which interact strongly with a rapidly varying environment and derive a Schrodinger-like equation which describes the time evolution of the average wave function. We show that the corresponding Hamiltonian can be…

General Physics · Physics 2009-11-07 R. Huerta , J. Wudka

We propose an approximate solution of the time-dependent Schr\"odinger equation using the method of stationary states combined with a variational matrix method for finding the energies and eigenstates. We illustrate the effectiveness of the…

Quantum Physics · Physics 2009-11-11 Paolo Amore , Alfredo Aranda , Francisco M. Fernandez , Hugh Jones

We discuss the relationship between exact solvability of the Schr\"{o}dinger equation with a position-dependent mass and the ordering ambiguity in the Hamiltonian operator within the frame of supersymmetric quantum mechanics. The…

Quantum Physics · Physics 2009-11-07 Besire Gonul , Bulent Gonul , Dilek Tutcu , Okan Ozer

We show that for a particular model, the quantum mechanical bootstrap is capable of finding exact results. We consider a solvable system with Hamiltonian $H=SZ(1-Z)S$, where $Z$ and $S$ satisfy canonical commutation relations. While this…

High Energy Physics - Theory · Physics 2024-02-07 Lewis Sword , David Vegh

We study solutions of the time dependent Schr\"odinger equation on Riemannian manifolds with oscillatory initial conditions given by Lagrangian states. Semiclassical approximations describe these solutions for small h (where h is the…

Mathematical Physics · Physics 2011-12-20 Roman Schubert

A powerful method for calculating the eigenvalues of a Hamiltonian operator consists of converting the energy eigenvalue equation into a matrix equation by means of an appropriate basis set of functions. The convergence of the method can be…

Quantum Physics · Physics 2007-05-23 Paolo Amore , Alfredo Aranda , Francisco Fernandez , Hugh Jones

Schr\"odinger equations with time-dependent potentials are of central importance in quantum physics and theoretical chemistry, where they aid in the simulation and design of systems and processes at atomic scales. Numerical approximation of…

Numerical Analysis · Mathematics 2018-06-04 Arieh Iserles , Karolina Kropielnicka , Pranav Singh

A method of solving the time-dependent Schr\"odinger equation is presented, in which a finite region of space is treated explicitly, with the boundary conditions for matching the wave-functions on to the rest of the system replaced by an…

Materials Science · Physics 2009-11-13 J. E. Inglesfield

A pseudo-Riemannian manifold contains an inherent Hamiltonian structure within the symplectic manifold in the cotangent bundle corresponding to the metric. Using this structure, it is possible to define a Hamiltonian, which can be…

General Relativity and Quantum Cosmology · Physics 2012-12-07 Ikjyot Singh Kohli

Described is n-level quantum system realized in the n-dimensional ''Hilbert'' space H with the scalar product G taken as a dynamical variable. The most general Lagrangian for the wave function and G is considered. Equations of motion and…

Mathematical Physics · Physics 2008-05-28 Vasyl Kovalchuk , Jan Jerzy Slawianowski

In this paper, we present efficient quantum algorithms that are exponentially faster than classical algorithms for solving the quantum optimal control problem. This problem involves finding the control variable that maximizes a physical…

Quantum Physics · Physics 2023-10-02 Xiantao Li , Chunhao Wang