901 research outputs found
A Universal Energy Functional for Trapped Fermi Gases with Large Scattering Length
Yoram Alhassid conjectured that the total energy of a harmonically trapped
two-component Fermi gas with large scattering length is a linear functional of
the occupation probabilities of single-particle energy eigenstates. We confirm
his conjecture and derive the functional explicitly. We show that the
functional applies to ALL smooth potentials having a minimum, not just harmonic
traps. We also calculate the occupation probabilities of high energy states.Comment: 4 page
Confinement-induced p-wave resonances from s-wave interactions
We show that a purely s-wave interaction in three dimensions (3D) can induce
higher partial-wave resonances in mixed dimensions. We develop two-body
scattering theories in all three cases of 0D-3D, 1D-3D, and 2D-3D mixtures and
determine the positions of higher partial-wave resonances in terms of the 3D
s-wave scattering length assuming a harmonic confinement potential. We also
compute the low-energy scattering parameters in the p-wave channel (scattering
volume and effective momentum) that are necessary for the low-energy effective
theory of the p-wave resonance. We point out that some of the resonances
observed in the Florence group experiment [Phys. Rev. Lett. 104, 153202 (2010)]
can be interpreted as the p-wave resonances in the 2D-3D mixed dimensions. Our
study paves the way for a variety of physics, such as Anderson localization of
matter waves under p-wave resonant scatterers.Comment: 19 pages, 8 figures; published versio
Migration flows management in Latvia
The present-day world features ever growing mobility - free movement of people, financial capital, markets and services. This mobility is enhanced and arranged by cross-national networks. The major instrument driving migration is modern technologies and information, including internet, communications and cheap air travels. The article makes insight into external migration trends of labour force and migration flows management prospects so as to discover the possible solutions for further formation of migration policy in Latvia.Migration, labour force, migration flows, migration policy., International Development, Labor and Human Capital, Public Economics, F22, J61,
Confinement-induced Efimov resonances in Fermi-Fermi mixtures
A Fermi-Fermi mixture of 40K and 6Li does not exhibit the Efimov effect in a
free space, but the Efimov effect can be induced by confining only 40K in one
dimension. Here the Efimov's three-body parameter is controlled by the
confinement length. We show that the three-body recombination rate in such a
system in the dilute limit has a characteristic logarithmic-periodic dependence
on the effective scattering length with the scaling factor 22.0 and can be
expressed by formulas similar to those for identical bosons in three
dimensions. The ultracold mixture of 40K and 6Li in the 1D-3D mixed dimensions
is thus a promising candidate to observe the Efimov physics in fermions.Comment: 5 pages, 4 figure
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