Temperature dependence of $p$-wave contacts in a harmonically trapped Fermi gas
Kenta Nagase, Hikaru Takahashi, Soki Oshima, Takashi Mukaiyama
Published: 2025/9/5
Abstract
We study the dependence of the $p$-wave contact $C_v$ on the Fermi temperature $T_F$ and reduced temperature $T/T_F$ based on the number of closed-channel molecules. From the anisotropic pattern of dissociated molecules, we resolve the narrow $|m|=0$ and $|m|=1$ dipolar splitting of the $p$-wave Feshbach resonance in $^6$Li, enabling the independent determination of the contact for the two components. As $T_F$ increases, the anisotropy is no longer resolved and the near-resonant contact scales linearly with $\sqrt{T_F}$, indicating the contribution of the normalized effective range $k_F R_{\rm{e}}$. The $T/T_F$ dependence across the attractive regime reveals opposite trends in the strongly and weakly interacting limits, which are accurately represented by the second-order virial expansion. Our results, together with estimates from the $p$-wave virial coefficient, provide a route toward a complete understanding of the thermodynamics of strongly interacting $p$-wave Fermi gases.