TY - JOUR
T1 - Spin-dipole mode in a trapped Fermi gas near unitarity
AU - Tajima, Hiroyuki
AU - Recati, Alessio
AU - Ohashi, Yoji
N1 - Funding Information:
H.T. thanks K. Iida, F. Scazza, R. Hanai, M. Pini, and M. Ota for useful discussions. This work was supported by a Grant-in-Aid for JSPS fellows (Grant No. 17J03975). A.R. acknowledges support from the Provincia Autonoma di Trento and the project of the National Institute for Nuclear Physics. Y.O. was supported by a Grant-in-Aid for Scientific Research from MEXT and JSPS in Japan (Grants No. JP18K11345, No. JP18H05406, and No. JP19K03689).
Publisher Copyright:
© 2020 American Physical Society.
PY - 2020/1/13
Y1 - 2020/1/13
N2 - We theoretically investigate the spin-dipole oscillation of a strongly interacting Fermi gas confined by a harmonic trapping potential. By using a diagrammatic strong-coupling theory combined with a local density approximation and a sum rule approach, we study the temperature dependence of the spin-dipole frequency near unitarity. The connection of the spin-dipole frequency with the spin susceptibility and the pairing correlations is exploited. While the spin-dipole frequency exactly coincides with the trap frequency in a noninteracting Fermi gas, it is shown to be strongly enhanced in the superfluid state, because of the suppression of the spin degree of freedom due to the spin-singlet Cooper-pair formation. In strongly interacting Fermi gases, such enhancement occurs even above the superfluid phase transition temperature, due to the strong pairing correlations.
AB - We theoretically investigate the spin-dipole oscillation of a strongly interacting Fermi gas confined by a harmonic trapping potential. By using a diagrammatic strong-coupling theory combined with a local density approximation and a sum rule approach, we study the temperature dependence of the spin-dipole frequency near unitarity. The connection of the spin-dipole frequency with the spin susceptibility and the pairing correlations is exploited. While the spin-dipole frequency exactly coincides with the trap frequency in a noninteracting Fermi gas, it is shown to be strongly enhanced in the superfluid state, because of the suppression of the spin degree of freedom due to the spin-singlet Cooper-pair formation. In strongly interacting Fermi gases, such enhancement occurs even above the superfluid phase transition temperature, due to the strong pairing correlations.
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U2 - 10.1103/PhysRevA.101.013610
DO - 10.1103/PhysRevA.101.013610
M3 - Article
AN - SCOPUS:85078117982
VL - 101
JO - Physical Review A
JF - Physical Review A
SN - 2469-9926
IS - 1
M1 - 013610/
ER -