Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Physical Review A

Many-body quantum Monte Carlo wave-function method for laser cooling

Tohya Hiroshima, Y. Yamamoto

Published Oct 1, 1997• 1 citation
Publisher

Abstract

We develop an auxiliary field approximation scheme for the many-body quantum Monte Carlo wave-function method to analyze numerically the system of cold atoms undergoing laser cooling. Numerical simulations for the three-dimensional Doppler cooling of bosonic and fermionic atoms are performed, which clearly exhibit the effects of quantum statistics.

DOI
10.1103/physreva.56.3077

Related papers

Laser cooling of atoms : Monte-Carlo wavefunction simulations

Renaud Chrétien

The purpose of our master thesis is to present an original synthesis of various works dealing with the Monte-Carlo wavefunction (MCWF) method in quantum optics and its applications to laser cooling of atoms with a particular focus on Doppler and Sisyphus cooling mechanisms. We introduce the MCWF method which is used to solve master equations describing the dynamics of open quantum systems in quantum optics. This method turns out to be much more efficient than a method based on the full integration of the density matrix. We perform laser cooling simulations in 1D both with a classical and a quantum treatment of the atomic centre-of-mass motion and investigate Doppler and Sisyphus cooling. Our numerical results turn out to be in very good agreement with those predicted by semiclassical theories, except for large detuning and/or low intensity laser where semiclassical theories fail. For such cases, our method provides a good alternative and predicts temperatures much larger than the recoil temperature. Finally, we also consider a classical treatment of the centre-of-mass motion and we compare the subsequent results with those obtained with a full quantum approach.

•Jun 23, 2014•3 citations

Many-body quantum Monte Carlo wave-function approach to the dissipative atom-field interaction

Ataç İmamoğlu, Li You

We develop a many-body quantum Monte Carlo wave-function approach to analyze the dissipative interaction of ultracold free atoms with the radiation field reservoir. A Markovian master equation for the identical atoms that neglects the dipole-dipole interaction is derived within the framework of quantum field theory. The effective Hamiltonian obtained by a decomposition of the master equation explicitly depends on the quantum statistics.

Physical Review A•Sep 1, 1994•25 citations

Effect of diffusion on laser cooling of atoms with long-range collisions

Andrew M. Smith II, Keith R. Burnett

An extension to a previous model [ J. Opt. Soc. Am. B8, 1594 ( 1991)], which described the collision between two atoms in a cooling laser field, is made, which allows diffusive effects to be analyzed. A method similar to that used in Monte Carlo studies is developed, except that the diffusion is now determined exactly at all times. This approach relies directly on making a local classical path approximation for the atoms’ trajectories. For the simple case of a single two-level atom in the cooling field, the energy of the atom reaches equilibrium at the Doppler limit, as one would expect. In the full collisional situation we make the assumption that each atom undergoes a series of binary collisions. For sufficiently high atomic densities these collisions provide a limit on the lowest temperature that may be achieved by the cooling process.

Journal of the Optical Society of America B•Aug 1, 1992•5 citations

Predictions of laser-cooling temperatures for multilevel atoms in three-dimensional polarization-gradient fields

Josh W. Dunn, Chris H. Greene

We analyze the dynamics of atom-laser interactions for atoms having multiple, closely spaced, excited-state hyperfine manifolds. The system is treated fully quantum mechanically, including the atom's center-of-mass degree of freedom, and motion is described in a polarization gradient field created by a three-dimensional laser configuration. We develop the master equation describing this system, and then specialize it to the low-intensity limit by adiabatically eliminating the excited states. We show how this master equation can be simulated using the Monte Carlo wave function technique, and we provide details on the implementation of this procedure. Monte Carlo calculations of steady state atomic momentum distributions for two fermionic alkaline earth isotopes, $^{25}\mathrm{Mg}$ and $^{87}\mathrm{Sr}$, interacting with a three-dimensional lin-\ensuremath{\perp}-lin laser configuration are presented, providing estimates of experimentally achievable laser-cooling temperatures.

arXiv:physics/0510268•Physical Review A•Mar 31, 2006•4 citations

Quantum Monte Carlo Algorithm Based on Two-Body Density Functional Theory for Fermionic Many-Body Systems: Application to He3

Balázs Hetényi, L. Brualla, Stefano Fantoni

We construct a quantum Monte Carlo algorithm for interacting fermions using the two-body density as the fundamental quantity. The central idea is mapping the interacting fermionic system onto an auxiliary system of interacting bosons. The correction term is approximated using correlated wave functions for the interacting system, resulting in an effective potential that represents the nodal surface. We calculate the properties of 3He and find good agreement with experiment and with other theoretical work. In particular, our results for the total energy agree well with other calculations where the same approximations were implemented but the standard quantum Monte Carlo algorithm was used.

arXiv:cond-mat/0503083•Physical Review Letters•Oct 19, 2004•22 citations

Monte Carlo wave functions and nonlinear master equations

Yvan Castin, Klaus Mølmer

The Monte Carlo wave-function method has recently proved to be an efficient tool in the analysis of linear dissipative quantum systems, i.e., systems with linear equations of motion for their density matrix. We generalize this method to systems with nonlinear master equations of a parametrized Lindblad form, which includes master equations obtained by Hartree-Fock approximations. Convergence properties of the algorithm are discussed in detail. The method is illustrated by a numerical analysis of the bosonic enhancement of laser cooling of trapped particles. \textcopyright{} 1996 The American Physical Society.

Physical Review A•Dec 1, 1996•24 citations
We develop an auxiliary field approximation scheme for the many-body quantum Monte Carlo wave-function method to analyze numerically the system of cold atoms undergoing laser cooling. Numerical simulations for the three-dimensional Doppler cooling of bosonic and fermionic atoms are performed, which clearly exhibit the effects of quantum statistics.
The purpose of our master thesis is to present an original synthesis of various works dealing with the Monte-Carlo wavefunction (MCWF) method in quantum optics and its applications to laser cooling of atoms with a particular focus on Doppler and Sisyphus cooling mechanisms. We introduce the MCWF method which is used to solve master equations describing the dynamics of open quantum systems in quantum optics. This method turns out to be much more efficient than a method based on the full integration of the density matrix. We perform laser cooling simulations in 1D both with a classical and a quantum treatment of the atomic centre-of-mass motion and investigate Doppler and Sisyphus cooling. Our numerical results turn out to be in very good agreement with those predicted by semiclassical theories, except for large detuning and/or low intensity laser where semiclassical theories fail. For such cases, our method provides a good alternative and predicts temperatures much larger than the recoil temperature. Finally, we also consider a classical treatment of the centre-of-mass motion and we compare the subsequent results with those obtained with a full quantum approach.
An extension to a previous model [ J. Opt. Soc. Am. B8, 1594 ( 1991)], which described the collision between two atoms in a cooling laser field, is made, which allows diffusive effects to be analyzed. A method similar to that used in Monte Carlo studies is developed, except that the diffusion is now determined exactly at all times. This approach relies directly on making a local classical path approximation for the atoms’ trajectories. For the simple case of a single two-level atom in the cooling field, the energy of the atom reaches equilibrium at the Doppler limit, as one would expect. In the full collisional situation we make the assumption that each atom undergoes a series of binary collisions. For sufficiently high atomic densities these collisions provide a limit on the lowest temperature that may be achieved by the cooling process.
We analyze the dynamics of atom-laser interactions for atoms having multiple, closely spaced, excited-state hyperfine manifolds. The system is treated fully quantum mechanically, including the atom's center-of-mass degree of freedom, and motion is described in a polarization gradient field created by a three-dimensional laser configuration. We develop the master equation describing this system, and then specialize it to the low-intensity limit by adiabatically eliminating the excited states. We show how this master equation can be simulated using the Monte Carlo wave function technique, and we provide details on the implementation of this procedure. Monte Carlo calculations of steady state atomic momentum distributions for two fermionic alkaline earth isotopes, 25Mg^{25}\mathrm{Mg}25Mg and 87Sr^{87}\mathrm{Sr}87Sr, interacting with a three-dimensional lin-\ensuremath{\perp}-lin laser configuration are presented, providing estimates of experimentally achievable laser-cooling temperatures.
We construct a quantum Monte Carlo algorithm for interacting fermions using the two-body density as the fundamental quantity. The central idea is mapping the interacting fermionic system onto an auxiliary system of interacting bosons. The correction term is approximated using correlated wave functions for the interacting system, resulting in an effective potential that represents the nodal surface. We calculate the properties of 3He and find good agreement with experiment and with other theoretical work. In particular, our results for the total energy agree well with other calculations where the same approximations were implemented but the standard quantum Monte Carlo algorithm was used.
The Monte Carlo wave-function method has recently proved to be an efficient tool in the analysis of linear dissipative quantum systems, i.e., systems with linear equations of motion for their density matrix. We generalize this method to systems with nonlinear master equations of a parametrized Lindblad form, which includes master equations obtained by Hartree-Fock approximations. Convergence properties of the algorithm are discussed in detail. The method is illustrated by a numerical analysis of the bosonic enhancement of laser cooling of trapped particles. \textcopyright{} 1996 The American Physical Society.