5 papers
Light-induced ultrafast magnetization dynamics in van der Waals antiferromagnetic CrSBr
Ali Kefayati, Yafei Ren
We investigate the ultrafast magnetization dynamics of semiconducting antiferromagnetic CrSBr using real-time time-dependent density functional theory. In zero magnetic field, lase…
Deciphering the origin of spin current in spintronic terahertz emitters and its imprint on their electromagnetic radiation via time-dependent density functional theory
Ali Kefayati, Yafei Ren, M. Benjamin Jungfleisch +3
Spin current flowing between femtosecond laser pulse (fsLP)-driven ferromagnetic metal and adjacent normal metal (NM) hosting strong spin-orbit coupling is invariably invoked to ex…
Charge and spin current pumping by ultrafast demagnetization dynamics
Jalil Varela-Manjarres, Ali Kefayati, M. Benjamin Jungfleisch +2
The surprising discovery of ultrafast demagnetization -- where electric field of femtosecond laser pulse couples to electrons of a ferromagnetic (FM) layer causing its magnetizatio…
Magnon spectrum of altermagnets beyond linear spin wave theory: Magnon-magnon interactions via time-dependent matrix product states vs. atomistic spin dynamics
Federico Garcia-Gaitan, Ali Kefayati, John Q. Xiao +1
The energy-momentum dispersion of magnons, as collective low-energy excitations of magnetic material, is computed from an effective quantum spin Hamiltonian but simplified via line…
Origins of electromagnetic radiation from spintronic terahertz emitters: A time-dependent density functional theory plus Jefimenko equations approach
Ali Kefayati, Branislav K. Nikolic
Microscopic origins of charge currents and electromagnetic (EM) radiation generated by them in spintronic THz emitters -- such as, femtosecond laser pulse-driven single magnetic la…