Density correlation functions and the spatial structure of the two-dimensional BEC-BCS crossover
Por:
Obeso-Jureidini, J. C., Romero-Rochin, V
Publicada:
11 abr 2022
Categoría:
Atomic and molecular physics, and optics
Resumen:
The spatial structure of a two-dimensional homogeneous mixture of
fermionic atoms in two hyperfine states is analyzed throughout the
BEC-BCS crossover. Within the BCS-Leggett mean-field model we consider
three functions: the pair wave function and the density-density
correlation functions between atoms of the same and of different
hyperfine states. For the correlation functions we derive analytical
expressions which allow one to unveil the rich spatial structure of the
superfluid. Mainly, we are able to study the large-distance behavior of
the three functions, which exhibits an exponential decay and a
well-defined oscillatory behavior. We report closedform expressions for
the correlation lengths and mean pair radius. Differences and
similarities emerge when comparing with the three-dimensional case.
Particularly, we find an expression for the large-distance correlation
length, in terms of the chemical potential and the gap, valid in two and
three dimensions, but whose dependence on the corresponding scattering
lengths differ significantly.
Filiaciones:
Obeso-Jureidini, J. C.:
Univ Nacl Autonoma Mexico, Inst Fis, Apartado Postal 20-364, Cd Mexico 01000, Mexico
Romero-Rochin, V:
Univ Nacl Autonoma Mexico, Inst Fis, Apartado Postal 20-364, Cd Mexico 01000, Mexico
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