2,540 research outputs found
Effective theory and universal relations for Fermi gases near a -wave interaction resonance
In this work, we present an effective field theory to describe a
two-component Fermi gas near a -wave interaction resonance. The effective
field theory is renormalizable by matching with the low energy -wave
scattering phase shift. Based on the effective field theory, we derive
universal properties of the Fermi gas by the operator product expansion method.
We find that beyond the contacts defined by adiabatic theorems, the asymptotic
expressions of the momentum distribution and the Raman spectroscopy involve two
extra contacts which provide additional information of correlations of the
system. Our formalism sets the stage for further explorations of many-body
effects in a -wave resonant Fermi gas. Finally we generalise our effective
field theory for interaction resonances of arbitrary higher partial waves.Comment: revised versio
Evidence for correlated states in a cluster of bosons with Rashba spin-orbit coupling
We study the ground state properties of spin-half bosons subjected to the
Rashba spin-orbit coupling in two dimensions. Due to the enhancement of the low
energy density of states, it is expected that the effect of interaction becomes
more important. After reviewing several possible ideal condensed states, we
carry out an exact diagonalization calculation for a cluster of the bosons in
the presence of strong spin-orbit coupling on a two-dimensional disk and reveal
strong correlations in its ground state. We derive a low-energy effective
Hamiltonian to understand how states with strong correlations become
energetically more favorable than the ideal condensed states.Comment: 23 pages, 6 figure
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