Spin Mass of an Electron Liquid

URL:http://link.aps.org/doi/10.1103/PhysRevLett.93.106601 DOI:10.1103/PhysRevLett.93.106601We show that in order to calculate correctly the spin current carried by a quasiparticle in an electron liquid one must use an effective “spin mass” ms that is larger than both the band mass mb, which determines the charge current, and the quasiparticle effective mass m*, which determines the heat capacity. We present two independent estimates of the spin mass enhancement, ms/mb, in two- and three-dimensional electron liquids, based on (i) previously calculated values of the Landau parameters and (ii) a recent theory of the dynamical local field factor in the spin channel. Both methods yield a significant spin mass enhancement, which is larger in two dimensions than in three.We gratefully acknowledge support by NSF Grants No. DMR-0074959 and No, DMR-0313681 and by DOE Grant No. DE-FG02-01ER45897