Quantum mechanical limitations to spin diffusion in the unitary Fermi gas
We compute spin transport in the unitary Fermi gas using the strong-coupling Luttinger-Ward theory. In the quantum degenerate regime the spin diffusivity attains a minimum value of $D_s \simeq 1.3 \hbar/m$ approaching the quantum limit of diffusion for a particle of mass $m$. Conversely, the spin dr...
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| Main Authors: | , |
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| Format: | Article (Journal) Chapter/Article |
| Language: | English |
| Published: |
2012
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| In: |
Arxiv
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| Online Access: | Verlag, kostenfrei, Volltext: http://arxiv.org/abs/1207.3103
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| Author Notes: | Tilman Enss, Physik Department, Technische Universität München, D-85747 Garching, Germany; Rudolf Haussmann, Fachbereich Physik, Universität Konstanz, D-78457 Konstanz, Germany |
| Summary: | We compute spin transport in the unitary Fermi gas using the strong-coupling Luttinger-Ward theory. In the quantum degenerate regime the spin diffusivity attains a minimum value of $D_s \simeq 1.3 \hbar/m$ approaching the quantum limit of diffusion for a particle of mass $m$. Conversely, the spin drag rate reaches a maximum value of $\Gamma_\sd \simeq 1.2 k_B T_F/\hbar$ in terms of the Fermi temperature $T_F$. The frequency-dependent spin conductivity $\sigma_s(\omega)$ exhibits a broad Drude peak, with spectral weight transferred to a universal high-frequency tail $\sigma_s(\omega \to\infty) = \hbar^{1/2}C/3\pi(m\omega)^{3/2}$ proportional to the Tan contact density $C$. For the spin susceptibility $\chi_s(T)$ we find no downturn in the normal phase. |
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| Item Description: | Gesehen am 23.11.2017 |
| Physical Description: | Online Resource |