76 citations · 236 across the 20 of their papers we have counts for
20 papers
Exact quantum dynamics of Fermi--Hubbard systems using the Gaussian phase-space representation with diffusion gauges
F Rousse, M Fasi, A Dmytryshyn +3
We use the Gaussian Phase-Space Representation to solve the real-time dynamic of interacting fermions in 1D, 2D, and 3D systems. The method is exact up to a spiking point, which re…
Rapidly-rotating quantum droplets confined in a harmonic potential
S. Nikolaou, G. M. Kavoulakis, M. Ogren
We consider a "symmetric" quantum droplet in two spatial dimensions, which rotates in a harmonic potential, focusing mostly on the limit of "rapid" rotation. We examine this proble…
Rotating quantum droplets confined in an anharmonic potential
S. Nikolaou, G. M. Kavoulakis, M. Ogren
We investigate the rotational properties of quantum droplets, which form in a mixture of two Bose-Einstein condensates, in the presence of an anharmonic trapping potential. We iden…
Nonlinearity managed vector solitons
F. Kh. Abdullaev, J. S. Yuldashev, M. Ogren
The evolution of vector solitons under nonlinearity management is studied. The averaged over strong and rapid modulations in time of the inter-species interactions vector Gross-Pit…
Random walks and moving boundaries: Estimating the penetration of diffusants into dense rubbers
Surendra Nepal, Magnus Ogren, Yosief Wondmagegne +1
For certain materials science scenarios arising in rubber technology, one-dimensional moving boundary problems (MBPs) with kinetic boundary conditions are capable of unveiling the…
Rotating quantum droplets confined in a harmonic potential
S. Nikolaou, G. M. Kavoulakis, M. Ogren
We investigate the rotational properties of a two-component, two-dimensional self-bound quantum droplet, which is confined in a harmonic potential and compare them with the well-kn…
Simulations of quantum dynamics with fermionic phase-space representations using numerical matrix factorizations as stochastic gauges
F Rousse, M Fasi, A Dmytryshyn +2
The Gaussian phase-space representation can be used to implement quantum dynamics for fermionic particles numerically. To improve numerical results, we explore the use of dynamical…
Correlated quantum dynamics of graphene
F. Rousse, O. Eriksson, M. Ogren
Phase-space representations are a family of methods for dynamics of both bosonic and fermionic systems, that work by mapping the system's density matrix to a quasi-probability dens…
Management of solitons in medium with competing cubic and quadratic nonlinearities
F. Kh. Abdullaev, J. S. Yuldashev, M. Ogren
Management of solitons in media with competing quadratic and cubic nonlinearities is investigated. Two schemes, using rapid modulations of a mismatch parameter, and of the Kerr non…
Stochastic solutions of Stefan problems
M. Ogren
This work deals with the one-dimensional Stefan problem with a general time-dependent boundary condition at the fixed boundary. Stochastic solutions are obtained using discrete ran…
Excitation spectrum of a mixture of two Bose gases confined in a ring potential with interaction asymmetry
A. Roussou, J. Smyrnakis, M. Magiropoulos +5
We study the rotational properties of a two-component Bose-Einstein condensed gas of distinguishable atoms which are confined in a ring potential using both the mean-field approxim…
Dimensional reduction in Bose-Einstein condensed clouds of atoms confined in tight potentials of any geometry and any interaction strength
P. Sandin, M. Ögren, M. Gulliksson +3
Motivated by numerous experiments on Bose-Einstein condensed atoms which have been performed in tight trapping potentials of various geometries (elongated and/or toroidal/annular),…
Numerical solution of the stationary multicomponent nonlinear Schrödinger equation with a constraint on the angular momentum
P. Sandin, M. Ogren, M. Gulliksson
We formulate a damped oscillating particle method to solve the stationary nonlinear Schrödinger equation (NLSE). The ground state solutions are found by a converging damped oscilla…
Perturbative Semiclassical Trace Formulae for Harmonic Oscillators
J. Moller-Andersen, M. Ogren
In this article we extend previous semiclassical studies by including more general perturbative potentials of the harmonic oscillator in arbitrary spatial dimensions. Our starting…
Self-consistent Ginzburg-Landau theory for transport currents in superconductors
M. Ogren, M. P. Soerensen, N. F. Pedersen
We elaborate on boundary conditions for Ginzburg-Landau (GL) theory in the case of external currents. We implement a self-consistent theory within the finite element method (FEM) a…
Zeno effect and switching of solitons in nonlinear couplers
F. Kh. Abdullaev, V. V. Konotop, M. Ogren +1
The Zeno effect is investigated for soliton type pulses in a nonlinear directional coupler with dissipation. The effect consists in increase of the coupler transparency with increa…
Stochastic simulations of fermionic dynamics with phase-space representations
M. Ogren, K. V. Kheruntsyan, J. F. Corney
A Gaussian operator basis provides a means to formulate phase-space simulations of the real- and imaginary-time evolution of quantum systems. Such simulations are guaranteed to be…
First-principles quantum dynamics for fermions: Application to molecular dissociation
M. Ogren, K. V. Kheruntsyan, J. F. Corney
We demonstrate that the quantum dynamics of a many-body Fermi-Bose system can be simulated using a Gaussian phase-space representation method. In particular, we consider the applic…
Role of spatial inhomogeneity in dissociation of trapped molecular condensates
Magnus Ogren, K. V. Kheruntsyan
We theoretically analyze dissociation of a harmonically trapped Bose-Einstein condensate of molecular dimers and examine how the spatial inhomogeneity of the molecular condensate a…
Uniform semiclassical trace formula for U(3) --> SO(3) symmetry breaking
M. Brack, M. Ögren, Y. Yu +1
We develop a uniform semiclassical trace formula for the density of states of a three-dimensional isotropic harmonic oscillator (HO), perturbed by a term . This term b…