English
Related papers

Related papers: Virtual states in the coupled-channel problems wit…

200 papers

Certain complex-contour (a.k.a. quantum-toboggan) generalizations of Schroedinger's bound-state problem are reviewed and studied in detail. Our key message is that the practical numerical solution of these atypical eigenvalue problems may…

Mathematical Physics · Physics 2011-02-15 Miloslav Znojil

Conventional weak-coupling Rayleigh-Schr\"odinger perturbation theory suffers from problems that arise from resonant coupling of successive orders in the perturbation series. Multiple-scale analysis, a powerful and sophisticated…

High Energy Physics - Theory · Physics 2009-10-30 Carl M. Bender , Luis M. A. Bettencourt

We show that nonlinear problems including nonlinear partial differential equations can be efficiently solved by variational quantum computing. We achieve this by utilizing multiple copies of variational quantum states to treat…

Quantum Physics · Physics 2020-01-15 Michael Lubasch , Jaewoo Joo , Pierre Moinier , Martin Kiffner , Dieter Jaksch

A precise dynamical characterization of quantum impurity models with multiple interacting orbitals is challenging. In quantum Monte Carlo methods, this is embodied by sign problems. A dynamical sign problem makes it exponentially difficult…

Mesoscale and Nanoscale Physics · Physics 2024-07-02 Andre Erpenbeck , Thomas Blommel , Lei Zhang , Wei-Ting Lin , Guy Cohen , Emanuel Gull

While historically many quantum mechanical simulations of molecular dynamics have relied on the Born-Oppenheimer approximation to separate electronic and nuclear behavior, recently a lot of interest has arisen towards quantum effects in…

Quantum Physics · Physics 2018-06-06 Simone Sturniolo

A numerical method of solving the one-dimensional Schrodinger equation for the regular and irregular continuum states using the phase-amplitude representation is presented. Our solution acquires the correct Dirac-delta normalization by…

Quantum Physics · Physics 2025-01-22 Daniel Hadush , Charles Weatherford

Hybrid classical-quantum algorithms aim at variationally solving optimisation problems, using a feedback loop between a classical computer and a quantum co-processor, while benefitting from quantum resources. Here we present experiments…

A detailed analysis has been made by R.Zavin and N.Moiseyev(2004 J. Phys. A: Math, Gen, \textbf{37} 4619) for the change of bound states into resonance states via coalescence of virtual states in a one-dimensional symmetric rectangular…

Quantum Physics · Physics 2008-10-21 M. Kawasaki , T. Maehara , M. Yonezawa

In order to reduce the computational cost of the simulation of electromagnetic responses in geophysical settings that involve highly heterogeneous media, we develop a multiscale finite volume method with oversampling for the quasi-static…

Computational Physics · Physics 2016-10-10 Luz Angelica Caudillo Mata , Eldad Haber , Christoph Schwarzbach

Quantum confinement is studied by numerically solving time-dependent Schr\"odinger equation. An imaginary-time evolution technique is employed in conjunction with the minimization of an expectation value, to reach the global minimum.…

Quantum Physics · Physics 2018-01-31 Amlan K. Roy

The possibility of using squeezed states in the recently suggested unidimensional continuous-variable quantum key distribution based on a single quadrature modulation is addressed. It is shown that squeezing of the signal states expands the…

Quantum Physics · Physics 2018-09-26 Vladyslav C. Usenko

The theory of open quantum systems lays the foundations for a substantial part of modern research in quantum science and engineering. Rooted in the dimensionality of their extended Hilbert spaces, the high computational complexity of…

Strongly Correlated Electrons · Physics 2024-06-10 Di Luo , Zhuo Chen , Juan Carrasquilla , Bryan K. Clark

The complex-scaling method can be used to calculate molecular resonances within the Born-Oppenheimer approximation, assuming the electronic coordinates are dilated independently of the nuclear coordinates. With this method, one will…

Quantum Physics · Physics 2021-06-16 Teng Bian , Sabre Kais

Numerical resolution of high-dimensional nonlinear PDEs remains a huge challenge due to the curse of dimensionality. Starting from the weak formulation of the Lawson-Euler scheme, this paper proposes a stochastic particle method (SPM) by…

Numerical Analysis · Mathematics 2025-02-11 Zhengyang Lei , Sihong Shao , Yunfeng Xiong

Quantum computers can be used to simulate nonlinear non-Hamiltonian classical dynamics on phase space by using the generalized Koopman-von Neumann formulation of classical mechanics. The Koopman-von Neumann formulation implies that the…

Quantum Physics · Physics 2020-10-27 Ilon Joseph

Multipartite entanglement detection is crucial for the develop of quantum information science and quantum computation, communication, simulation and metrology tasks. In contrast to experiments, where several handreds of qubits have been…

Quantum Physics · Physics 2024-11-06 Xiao-yu Chen

We explore two complementary modifications of the hybridization-expansion continuous-time Monte Carlo method, aiming at large multi-orbital quantum impurity problems. One idea is to compute the imaginary-time propagation using a matrix…

Strongly Correlated Electrons · Physics 2014-07-01 Hiroshi Shinaoka , Michele Dolfi , Matthias Troyer , Philipp Werner

The three-body scattering problem in Coulombic systems is widespread, however yet unresolved problem by the mathematically rigorous methods. In this work this long term challenge has been undertaken by combining distorted waves and…

Quantum Physics · Physics 2017-03-08 R. Lazauskas

A contracted quantum eigensolver (CQE) finds a solution to the many-electron Schr\"odinger equation by solving its integration (or contraction) to the 2-electron space -- a contracted Schr\"odinger equation (CSE) -- on a quantum computer.…

Quantum Physics · Physics 2022-05-05 Scott E. Smart , David A. Mazziotti

A novel method - the Virtual Ring Shear-Slip Mesh Update Method (VR-SSMUM) - for the efficient and accurate modeling of moving boundary or interface problems in the context of the numerical analysis of fluid flow is presented. We focus on…

Numerical Analysis · Mathematics 2018-04-11 Fabian Key , Lutz Pauli , Stefanie Elgeti