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arXiv · 1804.06529

Strong-Coupling and Finite Temperature Effects on $p$-wave Contacts

Abstract

We theoretically investigate strong-coupling and finite temperature effects on the p-wave contacts, as well as the asymptotic behavior of the momentum distribution in large momentum region in a one-component Fermi gas with a tunable p-wave interaction. Including p-wave pairing fluctuations within a strong-coupling theory, we calculate the p-wave contacts above the superfluid transition temperature $T_{\rm c}$ from the adiabatic energy relations. We show that while the p-wave contacts related to the scattering volume monotonically increases with increasing the interaction strength, one related to the effective range non-monotonically depends on interaction strength and its sign changes in the intermediate-coupling regime. The non-monotonic interaction dependence of these quantities is shown to originate from the competition between the increase of the cutoff momentum and the decrease of the coupling constant of the p-wave interaction with increasing the effective range. We also analyze the asymptotic form of the momentum distribution in large momentum region. In contrast to the conventional s-wave case, we show that the asymptotic behavior cannot be completely described by only the p-wave contacts, and the extra terms, which is not related to the thermodynamic properties, appear. Furthermore, in high temperature region, we find that the extra terms dominate the sub-leading term of the large-momentum distribution. We also directly compare our results with the recent experimental measurement, by including the effects of a harmonic trap potential within the local density approximation. We show that our model explains the dependence on the interaction strength of the p-wave contacts.

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BibTeXRIS

Daisuke Inotani, Yoji Ohashi. 2018-04-19. Strong-Coupling and Finite Temperature Effects on $p$-wave Contacts. https://doi.org/10.1103/physreva.98.023603

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