Universal sound diffusion in a strongly interacting Fermi gas

doi:10.1126/science.aaz5756

GSTDTAP > 气候变化

DOI	10.1126/science.aaz5756
	Universal sound diffusion in a strongly interacting Fermi gas
	Parth B. Patel; Zhenjie Yan; Biswaroop Mukherjee; Richard J. Fletcher; Julian Struck; Martin W. Zwierlein
	2020-12-04
发表期刊	Science
出版年	2020
英文摘要	A gas of strongly interacting fermionic atoms can serve as a model for systems with densities and energies spanning many orders of magnitude. This universality of physics comes about thanks to a property known as scale invariance. Patel et al. exploited this concept to draw universal conclusions about the attenuation of sound in such systems by studying a homogeneous gas of lithium-6 atoms at very low temperatures (see the Perspective by Schaefer). They found that below the superfluid transition, the sound diffusivity behaved not unlike what has been observed in helium-4, a fluid of strongly interacting bosons. Science , this issue p. [1222][1]; see also p. [1162][2] Transport of strongly interacting fermions is crucial for the properties of modern materials, nuclear fission, the merging of neutron stars, and the expansion of the early Universe. Here, we observe a universal quantum limit of diffusivity in a homogeneous, strongly interacting atomic Fermi gas by studying sound propagation and its attenuation through the coupled transport of momentum and heat. In the normal state, the sound diffusivity D monotonically decreases upon lowering the temperature, in contrast to the diverging behavior of weakly interacting Fermi liquids. Below the superfluid transition temperature, D attains a universal value set by the ratio of Planck’s constant and the particle mass. Our findings inform theories of fermion transport, with relevance for hydrodynamic flow of electrons, neutrons, and quarks. [1]: /lookup/doi/10.1126/science.aaz5756 [2]: /lookup/doi/10.1126/science.abb6155
领域	气候变化 ; 资源环境
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引用统计
文献类型	期刊论文
条目标识符	http://119.78.100.173/C666/handle/2XK7JSWQ/305841
专题	气候变化资源环境科学
推荐引用方式 GB/T 7714	Parth B. Patel,Zhenjie Yan,Biswaroop Mukherjee,et al. Universal sound diffusion in a strongly interacting Fermi gas[J]. Science,2020.
APA	Parth B. Patel,Zhenjie Yan,Biswaroop Mukherjee,Richard J. Fletcher,Julian Struck,&Martin W. Zwierlein.(2020).Universal sound diffusion in a strongly interacting Fermi gas.Science.
MLA	Parth B. Patel,et al."Universal sound diffusion in a strongly interacting Fermi gas".Science (2020).