English
Related papers

Related papers: Application of the variational $R$-matrix method t…

200 papers

A model for quantum tunnelling of a cluster comprising A identical particles, coupled by oscillator-type potential, through short-range repulsive potential barriers is introduced for the first time in the new symmetrized-coordinate…

Resonant tunnelling is studied numerically and analytically with the help of a three-well quantum one-dimensional time-independent model. The simplest cases are considered where the three-well potential is polynomial or piecewise constant.

Quantum Physics · Physics 2015-06-05 Jérémy Le Deunff , Olivier Brodier , Amaury Mouchet

After reexamining the above barrier diffusion problem where we notice that the wave packet collision implies the existence of {\em multiple} reflected and transmitted wave packets, we analyze the way of obtaining phase times for…

High Energy Physics - Phenomenology · Physics 2010-10-27 Alex E. Bernardini

By directly integrating the Schroedinger starting in the transmission region and working backwards through the barrier, the tunneling probability can be determined for arbitrary potential barriers. The method employs techniques familiar to…

Quantum Physics · Physics 2011-01-14 Andy Rundquist

We make a relativistic extension of the one-dimensional J-matrix method of scattering. The relativistic potential matrix is a combination of vector, scalar, and pseudo-scalar components. These are non-singular short-range potential…

Quantum Physics · Physics 2020-09-14 A. D. Alhaidari

Quantum tunneling across multiple barriers as yet is an unsolved problem for barrier numbers greater than five. The complexity of the mathematical analysis even for small number of barriers pushed it into the realms of Numerical Analysis.…

Quantum Physics · Physics 2013-10-31 Siddhant Das

We obtain the solutions for the tunneling zone of a one-dimensional electrostatic potential in the relativistic (Dirac to Klein-Gordon) wave equation regime when the incoming wave packet exhibits the possibility of being almost totally…

Quantum Physics · Physics 2009-11-10 Alex E. Bernardini

We present a unified theory of the variational Monte Carlo (VMC) and determinant quantum Monte Carlo (DQMC) methods using a novel density matrix formulation of VMC. We introduce an efficient algorithm for VMC to compute correlation…

Strongly Correlated Electrons · Physics 2018-10-02 Mohammad-Sadegh Vaezi , Abolhassan Vaezi

It was recently shown that a generalization of quantum Turing machines (QTMs), in which potentials are associated with elementary steps or transitions of the computation, generates potential distributions along computation paths of states…

Condensed Matter · Physics 2009-10-30 Paul Benioff

We describe a variational approximation method for efficient inference in large-scale probabilistic models. Variational methods are deterministic procedures that provide approximations to marginal and conditional probabilities of interest.…

Artificial Intelligence · Computer Science 2011-05-30 T. S. Jaakkola , M. I. Jordan

In this thesis the variational optimisation of the density matrix is discussed as a method in many-body quantum mechanics. This is a relatively unknown technique in which one tries to obtain the two-particle reduced density matrix directly…

Quantum Physics · Physics 2012-03-27 Brecht Verstichel

Quantum tunneling across double potential barriers is studied. With the assumption that the real space is a continuum, it is rigorously proved that large barriers of arbitrary shapes can be penetrated by low-energy particles with a…

Mesoscale and Nanoscale Physics · Physics 2024-02-02 Yong Yang

A variational ansatz for momentum eigenstates of translation invariant quantum spin chains is formulated. The matrix product state ansatz works directly in the thermodynamic limit and allows for an efficient implementation (cubic scaling in…

The resonant transmission of a moving particle which interacts with an one-dimensional array of N delta-function potentials is investigated. A suitable transfer matrix formulation is used to obtain the particle transmission. We give the…

Quantum Physics · Physics 2014-02-05 Guillermo Cordourier-Maruri , Virendra Gupta , Romeo de Coss

The reduced-density-matrix method is an promising candidate for the next generation electronic structure calculation method; it is equivalent to solve the Schr\"odinger equation for the ground state. The number of variables is the same as a…

Strongly Correlated Electrons · Physics 2011-06-27 Maho Nakata , Mituhiro Fukuda , Katsuki Fujisawa

We introduce a numerical variational method based on the Rayleigh-Ritz optimization principle for predicting two-dimensional self-trapped beams in nonlinear media. This technique overcomes the limitation of the traditional variational…

Optics · Physics 2018-04-04 Erick I. Duque , Servando Lopez-Aguayo , Boris A. Malomed

We introduce a unified formulation of variational methods for simulating ground state properties of quantum many-body systems. The key feature is a novel variational method over quantum circuits via infinitesimal unitary transformations,…

Quantum Physics · Physics 2009-11-13 Christopher M. Dawson , Jens Eisert , Tobias J. Osborne

Using the effective mass model for an electron and the dielectric continuum model, analytical solutions of the self-consistent Schr\"odinger-Poisson system of equations are obtained. Quantum mechanical theory of electronic stationary…

Quantum Physics · Physics 2018-12-21 I. V. Boyko

We propose two improvements to the well-known power series method for confined one-dimensional quantum-mechanical problems. They consist of the addition of a variational step were the energy plays the role of a variational parameter. We…

Quantum Physics · Physics 2016-02-25 Francisco M. Fernández

Reversible jump Markov chain Monte Carlo (RJMCMC) proposals that achieve reasonable acceptance rates and mixing are notoriously difficult to design in most applications. Inspired by recent advances in deep neural network-based normalizing…

Computation · Statistics 2023-02-28 Laurence Davies , Robert Salomone , Matthew Sutton , Christopher Drovandi