Superfluid equation of state of dilute composite bosons

Abstract

We present an exact theory of the BEC-BCS crossover in the BEC regime, which treats explicitely dimers as made of two fermions. We apply our framework, at zero temperature, to the calculation of the equation of state. We find that, when expanding the chemical potential in powers of the density n up to the Lee-Huang-Yang order, proportional to n^3/2, the result is identical to the one of elementary bosons in terms of the dimer-dimer scattering length a_M, the composite nature of the dimers appearing only in the next order term proportional to n^2 .

5 pages, 3 figures

References in corpus (3)

• Observation of Bose-Einstein Condensation of Molecules
• Weakly bound dimers of fermionic atoms
• Precision Measurements of Collective Oscillations in the BEC-BCS Crossover

Cited by in corpus (6)

• Theory of ultracold Fermi gases
• The Equation of State of a Low-Temperature Fermi Gas with Tunable Interactions
• Number of closed-channel molecules in the BEC-BCS crossover
• Nambu-Jona-Lasinio model description of weakly interacting Bose condensate and BEC-BCS crossover in dense QCD-like theories
• Strongly correlated Bose gases
• Excitation picture of an interacting Bose gas