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

arXiv:cond-mat/0504381 · Physical Review A

Quantum dynamics and statistical properties of atom-molecule Bose-Einstein condensates

Guangri Jin, Chul Koo Kim, Kyun Nahm

Published Oct 26, 2005• 20 citations
arXivHTMLPDF

Abstract

Based on a two-mode boson model, we study nonclassical properties of the atom-molecule Bose-Einstein condensate. The effects of nonlinear collisions on the dynamics of the molecular formation is studied both in classical and quantum treatments. We find that the conversion from atoms to molecules can be suppressed strongly due to nonlinearity induced localization of the atomic population. In addition, we study statistical properties of the atom-molecule condensed system by calculating the intensity correlation functions numerically. We find that the effect of nonlinearity leads to the appearance of superchaotic molecular pulses, while maintaining the atomic field sub-Poissonian. The joint quantum statistical properties of the atoms and the molecules always show antibunching.

DOI
10.1103/physreva.72.045602

Related papers

Higher-order nonclassical properties of atom-molecule Bose-Einstein Condensate

Sandip Kumar Giri, Kishore Thapliyal, Biswajit Sen +1 more

The transient quantum statistical properties of the atoms and molecules in an atom-molecule BEC system are investigated by obtaining a third-order perturbative solution of the Heisenberg's equations of motion corresponding to the Hamiltonian of an atom-molecule BEC system where two atoms can collide to form a molecule. Time dependent quantities like two boson correlation, entanglement, squeezing, antibunching, etc., are computed and their properties are compared. It is established that atom-molecule BEC system is highly nonclassical as lower-order and higher-order squeezing and antibunching in pure (atomic and molecular) modes, squeezing and antibunching in compound mode and lower-order and higher-order entanglement in compound mode can be observed in the atom-molecule BEC system. Exact numerical results are also reported and analytic results obtained using the perturbative technique are shown to coincide with the exact numerical results.

arXiv:1407.1780•Jul 7, 2014•0 citations

Chaos in coupled atom–molecular Bose–Einstein condensates

Haiming Deng, Jian‐Quan Huang, Dajun Lei +2 more

Abstract We investigate the chaotic dynamics of a coupled three-level atom–molecular Bose–Einstein condensate system composed by one molecular mode and two atomic modes. With the increase of atom–molecular coupling strength, we reveal the emergence of chaotic oscillations of the relative population difference between two atomic modes, which can be proven by the broad windows with a huge number of frequencies in spectral density and the chaotic trajectories in phase space diagrams. The different effects of initial states on atomic population oscillations are revealed, where for more particles in the initial state of the molecular model, chaos appears in the larger parameter region of system dynamics. Furthermore, we find that strong intermolecular interaction strength can suppress chaos resulting from strong atom–molecule coupling. This is due to the difficult transformation between atomic and molecular modes, as well as the relatively independent dynamic evolution of atoms and molecules.

Communications in Theoretical Physics•Mar 9, 2023•0 citations

Quantum Statistical Properties in Two-Species Bose–Einstein Condensates

Zhao-Xian Yu, Weigang Zhang

We have studied quantum statistical properties in a zero-temperature two-species Bose–Einstein condensate system in the presence of the nonlinear self-interaction of each species, the interspecies nonlinear interaction, and the Josephson-like tunneling interaction. It is found that the two condensates may periodically exhibit sub-Poissonian distribution. It is revealed that the correlation between the two condensates can be nonclassical, which means that there exists a violation of Cauchy–Schwartz inequality. The nonclassical effect about the correlation between the two condensates can be realized experimentally by properly preparing the total number of atoms in the two condensates.

Communications in Theoretical Physics•Jan 15, 2002•2 citations

Quantum oscillations in a two-mode atom-molecule Bose-Einstein condensate -- the discrete WKB approach

Jérôme Dorignac, Yu. B. Gaĭdideĭ, J. Chris Eilbeck +2 more

Quantum effects in a system of coupled atomic and molecular Bose-Einstein condensates in the framework of a two-mode model are studied numerically and analytically, using the discrete WKB approach. In contrast to the mean-field approximation, the WKB analytical results are in a very good agreement with numerical results. The quantum fluctuations of the atomic and molecular populations are calculated, and found to be of the same order of magnitude as their mean values.

arXiv:cond-mat/0511230•Nov 9, 2005•0 citations

Quantum dynamics of a molecular matter-wave amplifier

Jing Cheng, YiJing Yan

We study the quantum dynamics of a model of molecular matter-wave amplifier proposed by Search and Meystre [Phys. Rev. Lett. 93, 140405 (2004)], which employs a strongly damped optical cavity to convert an atomic Bose-Einstein condensate into vibrational ground-state molecules. By using the Monte Carlo wave-function method, we calculate the quantum evolution of the atomic and molecular matter waves. We find that the system always evolves into a pure ground-state molecular matter wave even if initially there was no ground-state molecules. Statistical properties of these atomic and molecular matter waves are also investigated. The final state of the molecular field is sub-Poissonian. Two-mode correlation functions exhibit anticorrelated properties.

Physical Review A•Mar 26, 2007•1 citation

First-principles quantum simulations of dissociation of molecular condensates: Atom correlations in momentum space

Craig M. Savage, Paul Schwenn, Karen V. Kheruntsyan

We investigate the quantum many-body dynamics of dissociation of a Bose-Einstein condensate of molecular dimers into pairs of constituent bosonic atoms and analyze the resulting atom-atom correlations. The quantum fields of both the molecules and atoms are simulated from first principles in three dimensions using the positive-$P$ representation method. This allows us to provide an exact treatment of the molecular field depletion and $s$-wave scattering interactions between the particles, as well as to extend the analysis to nonuniform systems. In the simplest uniform case, we find that the major source of atom-atom decorrelation is atom-atom recombination which produces molecules outside the initially occupied condensate mode. The unwanted molecules are formed from dissociated atom pairs with nonopposite momenta. The net effect of this process---which becomes increasingly significant for dissociation durations corresponding to more than about 40% conversion---is to reduce the atom-atom correlations. In addition, for nonuniform systems we find that mode mixing due to inhomogeneity can result in further degradation of the correlation signal. We characterize the correlation strength via the degree of squeezing of particle number-difference fluctuations in a certain momentum-space volume and show that the correlation strength can be increased if the signals are binned into larger counting volumes.

arXiv:cond-mat/0606345•Physical Review A•Sep 27, 2006•40 citations
Based on a two-mode boson model, we study nonclassical properties of the atom-molecule Bose-Einstein condensate. The effects of nonlinear collisions on the dynamics of the molecular formation is studied both in classical and quantum treatments. We find that the conversion from atoms to molecules can be suppressed strongly due to nonlinearity induced localization of the atomic population. In addition, we study statistical properties of the atom-molecule condensed system by calculating the intensity correlation functions numerically. We find that the effect of nonlinearity leads to the appearance of superchaotic molecular pulses, while maintaining the atomic field sub-Poissonian. The joint quantum statistical properties of the atoms and the molecules always show antibunching.
The transient quantum statistical properties of the atoms and molecules in an atom-molecule BEC system are investigated by obtaining a third-order perturbative solution of the Heisenberg's equations of motion corresponding to the Hamiltonian of an atom-molecule BEC system where two atoms can collide to form a molecule. Time dependent quantities like two boson correlation, entanglement, squeezing, antibunching, etc., are computed and their properties are compared. It is established that atom-molecule BEC system is highly nonclassical as lower-order and higher-order squeezing and antibunching in pure (atomic and molecular) modes, squeezing and antibunching in compound mode and lower-order and higher-order entanglement in compound mode can be observed in the atom-molecule BEC system. Exact numerical results are also reported and analytic results obtained using the perturbative technique are shown to coincide with the exact numerical results.
Abstract We investigate the chaotic dynamics of a coupled three-level atom–molecular Bose–Einstein condensate system composed by one molecular mode and two atomic modes. With the increase of atom–molecular coupling strength, we reveal the emergence of chaotic oscillations of the relative population difference between two atomic modes, which can be proven by the broad windows with a huge number of frequencies in spectral density and the chaotic trajectories in phase space diagrams. The different effects of initial states on atomic population oscillations are revealed, where for more particles in the initial state of the molecular model, chaos appears in the larger parameter region of system dynamics. Furthermore, we find that strong intermolecular interaction strength can suppress chaos resulting from strong atom–molecule coupling. This is due to the difficult transformation between atomic and molecular modes, as well as the relatively independent dynamic evolution of atoms and molecules.
We have studied quantum statistical properties in a zero-temperature two-species Bose–Einstein condensate system in the presence of the nonlinear self-interaction of each species, the interspecies nonlinear interaction, and the Josephson-like tunneling interaction. It is found that the two condensates may periodically exhibit sub-Poissonian distribution. It is revealed that the correlation between the two condensates can be nonclassical, which means that there exists a violation of Cauchy–Schwartz inequality. The nonclassical effect about the correlation between the two condensates can be realized experimentally by properly preparing the total number of atoms in the two condensates.
We study the quantum dynamics of a model of molecular matter-wave amplifier proposed by Search and Meystre [Phys. Rev. Lett. 93, 140405 (2004)], which employs a strongly damped optical cavity to convert an atomic Bose-Einstein condensate into vibrational ground-state molecules. By using the Monte Carlo wave-function method, we calculate the quantum evolution of the atomic and molecular matter waves. We find that the system always evolves into a pure ground-state molecular matter wave even if initially there was no ground-state molecules. Statistical properties of these atomic and molecular matter waves are also investigated. The final state of the molecular field is sub-Poissonian. Two-mode correlation functions exhibit anticorrelated properties.
We investigate the quantum many-body dynamics of dissociation of a Bose-Einstein condensate of molecular dimers into pairs of constituent bosonic atoms and analyze the resulting atom-atom correlations. The quantum fields of both the molecules and atoms are simulated from first principles in three dimensions using the positive-PPP representation method. This allows us to provide an exact treatment of the molecular field depletion and sss-wave scattering interactions between the particles, as well as to extend the analysis to nonuniform systems. In the simplest uniform case, we find that the major source of atom-atom decorrelation is atom-atom recombination which produces molecules outside the initially occupied condensate mode. The unwanted molecules are formed from dissociated atom pairs with nonopposite momenta. The net effect of this process---which becomes increasingly significant for dissociation durations corresponding to more than about 40% conversion---is to reduce the atom-atom correlations. In addition, for nonuniform systems we find that mode mixing due to inhomogeneity can result in further degradation of the correlation signal. We characterize the correlation strength via the degree of squeezing of particle number-difference fluctuations in a certain momentum-space volume and show that the correlation strength can be increased if the signals are binned into larger counting volumes.