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arXiv · 2110.00045

Spin waves in doped graphene: a time-dependent spin-density-functional approach to collective excitations in paramagnetic two-dimensional Dirac fermion gases

Matthew J. Anderson·Florent Perez·Carsten A. Ullrich
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Abstract

In spin-polarized itinerant electron systems, collective spin-wave modes arise from dynamical exchange and correlation (xc) effects. We here consider spin waves in doped paramagnetic graphene with adjustable Zeeman-type band splitting. The spin waves are described using time-dependent spin-density-functional response theory, treating dynamical xc effects within the Slater and Singwi-Tosi-Land-Sjolander approximations. We obtain spin-wave dispersions and spin stiffnesses as a function of doping and spin polarization, and discuss prospects for their experimental observation.

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Matthew J. Anderson, Florent Perez, Carsten A. Ullrich. 2021-09-30. Spin waves in doped graphene: a time-dependent spin-density-functional approach to collective excitations in paramagnetic two-dimensional Dirac fermion gases. https://doi.org/10.1103/physrevb.104.245422

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