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
ISSN: 24699926
Editorial
AMER PHYSICAL SOC, ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA, Estados Unidos America
Tipo de documento: Article
Volumen: 105 Número: 4
Páginas:
WOS Id: 000789240400001
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