Optical excitations in a non-ideal Bose gas

Abstract

Optical excitations in a Bose gas are demonstrated to be very sensitive to many-body effects. At low temperature the momentum relaxation is provided by momentum exchange collisions, rather than by elastic collisions. A collective excitation mode forms, which in a Boltzmann gas is manifest in a collision shift and dramatic narrowing of spectral lines. In the BEC state, each spectral line splits into two components. The doubling of the optical excitations results from the physics analogous to that of the second sound. We present a theory of the line doubling, and calculate the oscillator strengths and linewidth.

5 pages, 3 eps figures

References in corpus (5)

• Theory of Bose-Einstein condensation in trapped gases
• Bose-Einstein Condensation of Atomic Hydrogen
• Dynamical response of a Bose-Einstein condensate to a discontinuous change in internal state
• Cold Collision Frequency Shift of the 1S-2S Transition in Hydrogen
• First and Second Sound Modes of a Bose-Einstein Condensate in a Harmonic Trap

Cited by in corpus (27)

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• Internal waves and synchronized precession in a cold vapor
• Probing Bose-Einstein Condensation of Excitons with Electromagnetic Radiation
• Many-body treatment of the collisional frequency shift in fermionic atoms
• A Search for deviations from the inverse square law of gravity at nm range using a pulsed neutron beam
• Phase-Dependent Spontaneous Spin Polarization and Bifurcation Delay in Coupled Two-Component Bose-Einstein Condensates
• Cold Collision Frequency Shift of an Optical Spectrum of a Trapped Gas
• Normal-superfluid interaction dynamics in a spinor Bose gas
• Collisional Frequency Shifts of Absorption Lines in an Atomic Hydrogen Gas
• 1S-2S Spectrum of a Hydrogen Bose-Einstein Condensate
• Linear spin waves in a trapped Bose gas
• Stirring trapped atoms into fractional quantum Hall puddles
• Collective Excitations of a Two-Component Bose Condensate at Finite Temperature
• Spectroscopy of dipolar fermions in 2D pancakes and 3D lattices
• Collective dynamics of internal states in a Bose gas
• Gap and screening in Raman scattering of a Bose condensed gas
• Many-body physics in the radio frequency spectrum of lattice bosons
• Explanation of 100-fold reduction of spectral shifts for hydrogen on helium films
• Manifestation of a gap due to the exchange energy in a spinor condensate
• Candidate theories to explain the anomalous spectroscopic signatures of atomic H in molecular H${}_2$ crystals
• Transient dual-energy lasing in a semiconductor microcavity
• Probing the thermal atoms of a Bose gas through Raman transition
• Landau Damping of Spin Waves in Trapped Boltzmann Gases
• On the stability of the coherent state of a two-level atom Bose gas in the resonant laser field at zero temperature