Related papers: Algorithm for solving a pump-probe model for an ar…
We present a load balancing strategy for hybrid particle-mesh methods that is based on domain decomposition and element-local time measurement. This new strategy is compared to our previous approach, which assumes a constant weighting…
A quantum-mechanical Gaussian wave-packet approach to the theoretical description of nuclear motions in a condensed-phase environment is developed. General expressions for the time-dependent reduced density matrix are given for a harmonic…
We perform a comprehensive study of stability of a pumped atom laser in the presence of pumping, damping and outcoupling. We also introduce a realistic feedback scheme to improve stability by extracting energy from the condensate and…
Stable states in complex systems correspond to local minima on the associated potential energy surface. Transitions between these local minima govern the dynamics of such systems. Precisely determining the transition pathways in complex and…
We present a simple, analytic model for pump-probe spectroscopy in dilute atomic gases. Our model treats multilevel atoms, takes several broadening mechanisms into account and, with no free parameters, shows excellent agreement with…
In this work a generic model of \emph{multi-photon optics} is studied. It is considered $m$ pump and $n$ subharmonic fields. It shows how the multi-photon system, with direct and homodyne detection, can be obtained rigorously in the context…
We propose a numerical methodology for the simultaneous numerical simulation of four states of matter; gas, liquid, elastoplastic solids and plasma. The distinct, interacting physical processes are described by a combination of…
Numerical solution of partial differential equations on parallel computers using domain decomposition usually requires synchronization and communication among the processors. These operations often have a significant overhead in terms of…
We explore the coherent dynamics of a three-level V-system interacting with a thermal bath in the regime where thermal excitation occurs much faster than spontaneous decay. We present analytic solutions of the Bloch-Redfield quantum master…
In a recent experiment [Vochezer {\it et al.,} Phys. Rev. Lett. \textbf{120}, 073602 (2018)], a novel kind of hybrid atom-opto-mechanical system has been realized by coupling atoms in a lattice to a membrane. While such system promises a…
We study the influence of the angle between the two dipole transition moments on the group velocity for two kinds of three-level V-type systems with spontaneously generated coherence and incoherent pumping. The group velocity of the probe…
Atomic-scale phase-field modeling formulates the probability densities of atomic vibrations as Gaussian distributions and derives a free energy functional using variational Gaussian theory and interatomic potentials. This framework permits…
Simulation schemes that allow to change molecular representation in a subvolume of the simulation box while preserving the equilibrium with the surrounding introduce conceptual problems of thermodynamic consistency. In this work we present…
Optical pump-probe spectroscopy is a powerful tool to directly probe the carrier dynamics in materials down to sub-femtosecond resolution. To perform such measurement, while keeping the pump induced perturbation to the sample as small as…
We report on a two-fold increase of the $^{39}Ar$ loading rate in an atom trap by enhancing the generation of metastable atoms in a discharge source. Additional atoms in the metastable $1s_5$ level (Paschen notation) are obtained via…
In this work, we consider the problem of online (real-time, single-shot) estimation of static or slow-varying parameters along quantum trajectories in quantum dynamical systems. Based on the measurement signal of a continuously-monitored…
We solve the superradiant laser model in two limiting cases. First the stationary low-pumping regime is considered where a first-order phase transition in the semiclassical solution occurs. This discontinuity is smeared out in the quantum…
We describe a numerical algorithm for approximating the equilibrium-reduced density matrix and the effective (mean force) Hamiltonian for a set of system spins coupled strongly to a set of bath spins when the total system (system+bath) is…
We study a single incoherently pumped atom moving within an optical high-Q resonator in the strong coupling regime. Using a semiclassical description for the atom and field dynamics, we derive a closed system of differential equations to…
Phase balancing is essential to safe power system operation. We consider a substation connected to multiple phases, each with single-phase loads, generation, and energy storage. A representative of the substation operates the system and…