Fyzikální ústav Akademie věd ČR

Seminář Úterý, 19.01.2016 10:00 - 11:00

Přednášející: Karel Carva (Matematicko-fyzikální fakulta UK, Katedra fyziky kondenzovaných látek)
Místo: Přednáškový sál FZU na Slovance
Pořadatelé: Oddělení dielektrik

Abstrakt:

We provide a summary of our approach to various quantities in the field of spintronics and magnetization dynamics that can be calculated from first principles:

• related to non-relativistic spin-dependent transport (magnetoresistance, spin-transfer torque [1]),

• to relativistic effects (magnetic anisotropy, anisotropic magnetoresistance, anomalous Hall conductivity [2]),

• phonon related (electron-phonon lifetimes, temperature dependent resistivities [3]),

• affecting magnetization (exchange constants, spin-flip rates [4]).

The last set of quantities can be used for example to study non-equilibrium magnetization dynamics induced by femtosecond lasers. We employ it to calculate for how long times are different subsystems (magnetic, electronic, phononic) not in equilibrium with each other and to see which effects contribute mostly to demagnetization [3,4].

[1] Carva, K; Turek, I, Phys. Rev. B 76, 104409 (2007).

[2] Turek, I.; Kudrnovsky, J.; Carva, K., Phys. Rev. B 86, 174430 (2012).

[3] Carva, K.; Battiato, M.; Oppeneer, P. M., Phys. Rev. Lett. 107, 207201 (2011).

[4] Frietsch, B.; Bowlan, J.; Carley, R.; et al., Nat. Comm. 6, 8262 (2015).