Zero Sound in Dipolar Fermi Gases
نویسندگان
چکیده
We study the propagation of sound in a homogeneous dipolar gas at zero temperature, known as zero sound. We find that below a critical dipolar interaction, undamped sound propagation is possible only in a range of solid angles around the direction of polarization of the dipoles. For larger interaction strength, zero sound propagates in all directions, but its nature changes as a function of direction. In particular, there appears a transverse mode for the perpendicular propagation direction, which resembles the transverse mode in liquid He-3. We explain how these properties arise as a result of the anisotropic dipolar interaction. Zero Sound in Dipolar Fermi Gases 2
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