Spin Coulomb Drag in Quasi‐One‐Dimensional Electron Gas: Dynamical Spin Correlation and Spin‐Polarization Effects

The spin drag rate () in a quasi‐one‐dimensional electron gas (Q1DEG) is calculated for different electron coupling parameter (), temperature (), and spin‐polarization () using the dynamical mean‐field theory of Hasegawa and Shimizu (the qSTLS theory); , being the number density of ‐spin electrons. It is found that at a given , increases with rise in both for the unpolarized () and partially spin‐polarized () Q1DEG. On the other hand, at a fixed , the ‐variation of exhibits a monotonically decreasing trend for the unpolarized system, while a peaked structure develops for the partially polarized case. Furthermore, drops drastically for a given and as the system undergoes a paramagnetic‐ferromagnetic () phase transition. Interestingly, the rate of increase of with shows relatively a mild increment as approaches its critical value for transition to a spin‐density wave (SDW) phase at a given temperature. The spin‐plasmon energy is also reported and it is found that it decreases significantly with increase in at fixed and , while it increases with rise in and/or for finite .