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arXiv · 1101.3373

Effects of interaction and polarization on spin-charge separation: A time-dependent spin-density-functional theory study

Gao Xianlong
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Abstract

We calculate the nonequilibrium dynamic evolution of a one-dimensional system of two-component fermionic atoms after a strong local quench by using a time-dependent spin-density-functional theory. The interaction quench is also considered to see its influence on the spin-charge separation. It is shown that the charge velocity is larger than the spin velocity for the system of on-site repulsive interaction (Luttinger liquid), and vise versa for the system of on-site attractive interaction (Luther-Emery liquid). We find that both the interaction quench and polarization suppress the spin-charge separation.

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Gao Xianlong. 2011-01-18. Effects of interaction and polarization on spin-charge separation: A time-dependent spin-density-functional theory study. https://doi.org/10.1103/physrevb.81.104306

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