Collective Excitations of Rotating Dipolar Fermi Gases in the Fractional Quantum Hall Regime

Szu-Cheng Cheng

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arXiv · 0808.0439

Collective Excitations of Rotating Dipolar Fermi Gases in the Fractional Quantum Hall Regime

Szu-Cheng Cheng

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Abstract

We apply the magneto-roton theory of the fractional quantum Hall effect to study the collective excitation spectrum of rotating dipolar Fermi gases. The predicted spectrum has a finite energy gap in the long wavelength limit and a roton minimum at finite wave vector. The roton minimum being deepened from filling factor 1/3 to filling factor 1/5 is a signature of incipient crystallization near filling factor 1/7. We also demonstrate that there are no low-lying single-particle excitations below the roton mode. The fractional-quantum-Hall fluid rotating dipolar fermions behaves as an incompressible superfluid at low temperature.

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Szu-Cheng Cheng. 2008-08-22. Collective Excitations of Rotating Dipolar Fermi Gases in the Fractional Quantum Hall Regime. https://arxiv.org/abs/0808.0439

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