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Related papers: Demkov-Kunike model in cold molecule formation

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We study the dynamics of a nonlinear two-level crossing model with a cubic modification of the linear Landau-Zener diabatic energies. The solutions are expressed in terms of the bi-confluent Heun functions --- the generalization of the…

Quantum Physics · Physics 2019-12-06 Chon-Fai Kam , Yang Chen

Based on a chain of BBGKI equations with a modified boundary condition that takes into account multiparticle correlations, kinetic equations in the approximate "pairs" collisions and in the polarization approximation, taking into account…

Statistical Mechanics · Physics 2022-10-13 M. Tokarchuk

We analyze the long-time quantum dynamics of degenerate parametric down-conversion from an initial sub-harmonic vacuum (spontaenous down-conversion). Standard linearization of the Heisenberg equations of motions fails in this case, since it…

Quantum Physics · Physics 2015-06-26 Michael Fleischhauer , Oliver Veits

We study a generalized cold atom Bose Hubbard model, where the periodic optical potential is formed by a cavity field with quantum properties. On the one hand the common coupling of all atoms to the same mode introduces cavity mediated long…

Quantum Physics · Physics 2009-11-11 Christoph Maschler , Helmut Ritsch

We provide a practical approach to the molecular production via linear downward sweeps of Feshbach resonances in degenerate Fermi gases containing incoherent mixtures of two atomic spin states. We show that the efficiency of the association…

Other Condensed Matter · Physics 2007-05-23 Jan Chwedenczuk , Krzysztof Goral , Thorsten Koehler , Paul S. Julienne

We study a bulk fermionic dipolar molecular gas in the quantum degenerate regime confined in a two-dimensional geometry. We consider two rotational states that encode a spin 1/2 degree of freedom. We derive a long-range interacting XXZ…

Using numerical calculations, we compare the collective transition probabilities of many spins in random magnetic fields, subject to either frequent projective measurements, frequent phase modulations, or a mix of modulations and…

Quantum Physics · Physics 2014-08-04 Wenxian Zhang , A. G. Kofman , Jun Zhuang , J. Q. You , Franco Nori

The physics of interacting nuclear spins arranged in a crystalline lattice is typically described using a thermodynamic framework: a variety of experimental studies in bulk solid-state systems have proven the concept of a spin temperature…

Mesoscale and Nanoscale Physics · Physics 2009-07-21 P. Maletinsky , M. Kroner , A. Imamoglu

Attempts to understand zero temperature phase transitions have forced physicists to consider a regime where the standard paradigms of condensed matter physics break down [1-4]. These quantum critical systems lack a simple description in…

Quantum Gases · Physics 2012-07-04 Kaden R. A. Hazzard , Erich J. Mueller

The state of art in studying thermodynamic properties of hot and dense nuclear matter is reviewed with the special emphasis on the confinement-deconfinement transition between hadron matter and quark-gluon plasma. The most popular models…

High Energy Physics - Phenomenology · Physics 2011-07-19 V. I. Yukalov , E. P. Yukalova

We establish a connection between macroscopic "heating or cooling" of a finite many-body quantum system and the non-adiabatic Landau-Zener-St\"{u}ckelberg transitions between its quantum states. We have considered the well-known Nilsson…

Nuclear Theory · Physics 2019-11-12 Nishchal R. Dwivedi , Sudhir R. Jain

We present a nonequilibrium kinetic theory describing atom-molecule population dynamics in a two-component Fermi gas with a Feshbach resonance. Key collision integrals emerge that govern the relaxation of the atom-molecule mixture to…

Other Condensed Matter · Physics 2009-11-10 J. E. Williams , T. Nikuni , N. Nygaard , C. W. Clark

The reduced dynamics of an atomic qubit coupled both to its own quantized center of mass motion through the spatial mode functions of the electromagnetic field, as well as the vacuum modes, is calculated in the influence functional…

Quantum Physics · Physics 2009-11-10 S. Shresta , B. L. Hu

We study the dynamics of a symmetric two-level system strongly coupled to a broadened harmonic mode. Upon mapping the problem onto a spin-boson model with peaked spectral density, we show how analytic solutions can be obtained, at arbitrary…

Statistical Mechanics · Physics 2009-11-13 F. Nesi , M. Grifoni , E. Paladino

We present a general approach to incorporate hadronic as well as quark degrees of freedom in a unified approach. This approach implements the correct degrees of freedom at high as well as low temperatures and densities. An effective…

Nuclear Theory · Physics 2011-02-14 S. Schramm , J. Steinheimer

We study an ultracold gas of neutral atoms subject to the periodic optical potential generated by a high-$Q$ cavity mode. In the limit of very low temperatures, cavity field and atomic dynamics require a quantum description. Starting from a…

Quantum Physics · Physics 2008-02-15 Christoph Maschler , Igor B. Mekhov , Helmut Ritsch

A recent experiment reported for the first time the preparation of a Fermi degenerate gas of polar molecules and observed a suppression of their chemical reaction rate compared to the one expected from a purely classical treatment. While it…

Quantum Gases · Physics 2021-01-04 Peiru He , Thomas Bilitewski , Chris H. Greene , Ana Maria Rey

The quantum theory of the cold atom micromaser including the effects of gravity is established in the general case where the cavity mode and the atomic transition frequencies are detuned. We show that atoms which classically would not reach…

Quantum Physics · Physics 2008-06-13 John Martin , Thierry Bastin

We study the thermophysical properties of dense helium plasmas by using quantum molecular dynamics and orbital-free molecular dynamics simulations, where densities are considered from 400 to 800 g/cm$^{3}$ and temperatures up to 800 eV.…

Materials Science · Physics 2011-06-27 Cong Wang , Xian-Tu He , Ping Zhang

We have developed and implemented a new quantum molecular dynamics approximation that allows fast and accurate simulations of dense plasmas from cold to hot conditions. The method is based on a carefully designed orbital-free implementation…

Plasma Physics · Physics 2015-06-22 Travis Sjostrom , Jerome Daligault