Viscous spin exchange torque on precessional magnetization in $(\mathrm{LaMnO}_3)_{2n}/(\mathrm{SrMnO}_3)_{n}$ superlattices

Autor:	Zhao, H. B., Smith, K. J., Fan, Y., Lüpke, G., Bhattacharya, A., Bader, S. D., Warusawithana, M., Zhai, X., Eckstein, J. N.
Rok vydání:	2007
Předmět:	Condensed Matter - Materials Science Condensed Matter - Strongly Correlated Electrons
Druh dokumentu:	Working Paper
DOI:	10.1103/PhysRevLett.100.117208
Popis:	Photoinduced magnetization dynamics is investigated in chemically ordered $(\mathrm{LaMnO}_3)_{2n}/(\mathrm{SrMnO}_3)_n$ superlattices using the time-resolved magneto-optic Kerr effect. A monotonic frequency-field dependence is observed for the $n=1$ superlattice, indicating a single spin population consistent with a homogeneous hole distribution. In contrast, for $n\geq2$ superlattices, a large precession frequency is observed at low fields indicating the presence of an exchange torque in the dynamic regime. We propose a model that ascribes the emergence of exchange torque to the coupling between two spin populations -- viscous and fast spins. Comment: 5 pages, 4 figures
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/0706.2157 Zobrazit plný text záznamu View this record from Arxiv