Acceleration of the precession frequency for optically-oriented electron spins in ferromagnetic/semiconductor hybrids

Autor(es)

Moraes, F. C. D. ^[1] ; Ullah, S. ^{[1, 2]} ; Balanta, M. A. G. ^[3] ; Iikawa, F. ^[3] ; Danilov, Y. A. ^[4] ; Dorokhin, V, M. ; Vikhrova, O. V. ^[5] ; Zvonkov, B. N. ^[5] ; Hernandez, F. G. G. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Fis, BR-05508090 Sao Paulo, SP - Brazil

^[2] Gomal Univ, Dept Phys, Dera Ismail Khan 29220, KP - Pakistan

^[3] Univ Estadual Campinas, Inst Fis Gleb Wataghin, BR-13083859 Campinas, SP - Brazil

^[4] Nizhnii Novgorod State Univ, Physicotech Res Inst, Nizhnii Novgorod 603950 - Russia

^[5] Dorokhin, M., V, Nizhnii Novgorod State Univ, Physicotech Res Inst, Nizhnii Novgorod 603950 - Russia

• Tipo de documento: Artigo Científico
• Fonte: SCIENTIFIC REPORTS; v. 9, MAY 13 2019.
• Citações Web of Science: 0

Resumo

Time-resolved Kerr rotation measurements were performed in InGaAs/GaAs quantum wells nearby a doped Mn delta layer. Our magneto-optical results show a typical time evolution of the optically oriented electron spin in the quantum well. Surprisingly, this is strongly affected by the Mn spins, resulting in an increase of the spin precession frequency in time. This increase is attributed to the variation in the effective magnetic field induced by the dynamical relaxation of the Mn spins. Two processes are observed during electron spin precession: a quasi-instantaneous alignment of the Mn spins with photo-excited holes, followed by a slow alignment of Mn spins with the external transverse magnetic field. The first process leads to an equilibrium state imprinted in the initial precession frequency, which depends on pump power, while the second process promotes a linear frequency increase, with acceleration depending on temperature and external magnetic field. This observation yields new information about exchange process dynamics and on the possibility of constructing spin memories, which can rapidly respond to light while retaining information for a longer period. (AU)

• Processo FAPESP: 16/16365-6 - Nanoestruturas de semicondutoras III-V e suas propriedades ópticas
• Beneficiário: Fernando Iikawa
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 15/16191-5 - Pesquisas em novos materiais envolvendo campos magnéticos intensos e baixas temperaturas
• Beneficiário: Gennady Gusev
• Modalidade de apoio: Auxílio à Pesquisa - Temático