Dynamics of Fluctuactions in the BCS-BEC Crossover in Superfluid Fermi Gases

27th International Conference on Low Temperature Physics

Vivas C, H.^1

Departamento de Física, Universidad Nacional de Colombia, Sede Manizales

A.A. 127, Colombia^1

关键词: BCS-BEC crossover;    Collective modes;    Explicit formula;    Finite temperatures;    Mean field approximation;    Particle-particle interactions;    Superfluid Fermi gas;    Time dependent Ginzburg-Landau equations;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/568/1/012024/pdf
DOI  :  10.1088/1742-6596/568/1/012024

来源: IOP

【 摘 要 】

The BCS-BEC crossover phenomenon in a 3D attractive Fermi gas is revisited by using finite temperature Green functions formalism derived from the quantum path integral technique and Mean Field Approximation (MFA). Collective modes for weak and strong coupling particle-particle interaction g are obtained after recovering the dynamical coefficients in the nonlinear Time Dependent Ginzburg Landau (TDGL) equation, and numerically simulated under those particular states for the filling energy g ∼ 0 and order parameter Δ(x,τ) ∼ Δ0. Explicit formulas for the first order average fluctuations η2q,ω and the scaling law for the thermal energy associated to the non-linear collective modes are also reported.