The hierarchy of excitation lifetimes in two-dimensional Fermi gases
Name
1905.03751.pdf
Description
Submitted version
Size
1.5 MB
Format
Unknown
Checksum (MD5)
d1a75e82ac93d6c1e03817c019d13c3c
Author(s)
Ledwith, Patrick J.
Guo, Haoyu
Levitov, Leonid
Date Issued
2019
Journal
Annals of Physics
Publisher
Elsevier BV
Version
Original manuscript
Abstract
© 2019 Momentum-conserving quasiparticle collisions in two-dimensional Fermi gases give rise to a large family of exceptionally long-lived excitation modes. The lifetimes of these modes exceed by a factor (TF∕T)2≫1 the conventional Landau Fermi-liquid lifetimes τ∼TF∕T2. The long-lived modes have a distinct angular structure, taking the form of cosmθ and sinmθ with odd m values for a circular Fermi surface, with relaxation rate dependence on m of the form m4logm, valid at not-too-large m. In contrast, the even-m harmonics feature conventional lifetimes with a weak m dependence. The long-time dynamics, governed by these modes, occurs at “non-Fermi-liquid” timescales, taking values as large as τ∼TF3∕T4. The hierarchy of timescales, short and long, leads to unusual long-time memory effects, defining an intriguing transport regime that lies between the conventional ballistic and hydrodynamic regimes.
MIT Department
Massachusetts Institute of Technology. Department of Physics
Terms of Use
Creative Commons Attribution-NonCommercial-NoDerivs License
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1016/J.AOP.2019.167913
