Ultracold Metastable Calcium Ensembles , a Medium for Matter Wave Amplification ?

Ultracold metastable calcium atoms in a bichromatic magneto-optical trap

Momentum distribution functions in ensembles: the inequivalence of microcannonical and canonical ensembles in a finite ultracold system.

It is demonstrated in many thermodynamic textbooks that the equivalence of the different ensembles is achieved in the thermodynamic limit. In this present work we discuss the inequivalence of microcanonical and canonical ensembles in a finite ultracold system at low energies. We calculate the microcanonical momentum distribution function (MDF) in a system of identical fermions (bosons). We find...

Phase-coherent amplification of matter waves

Phase-coherent matter-wave amplification was demonstrated using Bose- Einstein-condensed rubidium-87 atoms. A small seed matter wave was created with coherent optical Bragg diffraction. Amplification of this seed matter wave was achieved by using the initial condensate as a gain medium through the superradiance effect. The coherence properties of the amplified matter wave, studied with a matter...

Frequency shifts of photoassociative spectra of ultracold metastable Helium atoms : a new measurement of the s-wave scattering length

– We observe light-induced frequency shifts in one-color photoassociative spectra of magnetically trapped He atoms in the metastable 2S1 state. A pair of ultracold spinpolarized 2S1 helium atoms is excited into a molecular bound state in the purely long range 0+u potential connected to the 2 S1−2 P0 asymptote. The shift arises from the optical coupling of the molecular excited bound state with ...

Multi fluidity and Solitary wave stability in cold quark matter: core of dense astrophysical objects

Considering the magneto-hydrodynamic equations in a non-relativistic multi uid framework, we study the behavior of small amplitude perturbations in cold quark matter. Magneto-hydrodynamic equations, along with a suitable equation of state for the cold quark matter, are expanded using the reductive perturbation method. It is shown that in small amplitude approximation, such a medium should be co...