arXiv subjects

G. M. Genkin

Publications and source records attributed to G. M. Genkin.

5 recordsLinked to original sources

arXiv2005

Tuning the superfluid - Mott insulator transition in a resonantly strongly driven Bose - Einstein condensate in an optical lattice

We have studied the superfluid - Mott insulator transition in a BEC confined in an optical lattice and driven by an additional external electromagnetic field, which excites another internal state. It is shown that due to resonant strong driving the critical values of the transition parameter depend on external field parameters (the Rabi frequency and the detuning from resonance) and can be tuned to a given value. It is also shown that for driven system there are two optical potential depths at a phase transition which are always more than without driving.

cond-mat.other↗

arXiv2005

Breached superfluidity of fermionic atoms in magnetic field

We derived the energy gap of a breached pairing superfluidity phase of fermionic atoms in an external magnetic field in Feshbach resonance experiments which is determined by the magnetic - field detuning from the Feshbach resonance. We show that a BCS superfluid state exists only for the magnetic - field detuning smaller than one critical, and this critical magnetic - field detuning is determined by the equality of the Zeeman energy splitting for the magnetic - field detuning to the energy gap $ Δ_0 $.

physics.atom-ph↗

arXiv2005

Destroying the superfluid state of fermionic atoms by the magnetic field in Feshbach resonance experiments

We show that the superfluid state (SF) of fermionic atoms exist only for the magnetic fields lesser than the critical magnetic field. This critical magnetic field is determined by the equality of the Zeeman energy splitting for atoms with different spin projections to the energy gap of fermionic atoms without a magnetic field. For magnetic fields usually using in Feshbach resonance experiments a SF state is lost because these fields are much more than the critical field. We show that the transition temperature $ T_c $ of the SF state decreases as the magnetic field increases.

physics.atom-ph↗

arXiv2004

Manipulating the scattering length of a Bose - Einstein condensate in an amplitude - modulated optical lattice

The scattering length in a BEC confined in an amplitude - modulated optical lattice can be manipulated by the modulation strength. Two standing laser waves of main and sideband frequencies of an optical lattice induce a Raman transition; due to resonant Raman driving the effective scattering length depends on the modulation strength and the detuning from resonance and can be tuned to a given value.

physics.atom-ph↗

arXiv2003

Manipulating the superfluid - Mott insulator transition of a Bose - Einstein condensate in an amplitude - modulated optical lattice

The superfluid - Mott insulator transition in a BEC confined in an amplitude - modulated optical lattice can be manipulated by the modulation strength. Two standing laser waves of main and sideband frequencies of an optical lattice induce a Raman transition; due to resonant Raman driving the critical value of the transition parameter depends on the modulation strength and the detuning from resonance and can be tuned to a given value. It is shown that there is an interval of the initial MI phase, in which a modulation switches the MI phase to the SF phase.

cond-mat↗