| Texto completo | |
| Autor(es): Mostrar menos - |
Lafrentz, M.
[1]
;
Brunne, D.
[1]
;
Kaminski, B.
[1]
;
Pavlov, V. V.
[2]
;
Henriques, A. B.
[3]
;
Pisarev, R. V.
[2]
;
Yakovlev, D. R.
[1, 2]
;
Springholz, G.
[4]
;
Bauer, G.
[4]
;
Abramof, E.
[5]
;
Rappl, P. H. O.
[5]
;
Bayer, M.
[1]
Número total de Autores: 12
|
| Afiliação do(s) autor(es): | [1] Tech Univ Dortmund, D-44221 Dortmund - Germany
[2] Russian Acad Sci, AF Ioffe Phys Tech Inst, St Petersburg 194021 - Russia
[3] Univ Sao Paulo, Inst Fis, BR-05315970 Sao Paulo - Brazil
[4] Johannes Kepler Univ Linz, Inst Halbleiter & Festkorperphys, A-4040 Linz - Austria
[5] LAS INPE, BR-12227010 Sao Jose Dos Campos, SP - Brazil
Número total de Afiliações: 5
|
| Tipo de documento: | Artigo Científico |
| Fonte: | Physical Review B; v. 82, n. 23 DEC 13 2010. |
| Citações Web of Science: | 10 |
| Assunto(s): | Semicondutores Geração de segundo harmônico Spin |
| Resumo | |
EuTe possesses the centrosymmetric crystal structure m3m of rocksalt type in which the second-harmonic generation is forbidden in electric dipole approximation but the third-harmonic generation (THG) is allowed. We studied the THG spectra of this material and observed several resonances in the vicinity of the band gap at 2.2-2.5 eV and at higher energies up to 4 eV, which are related to four-photon THG processes. The observed resonances are assigned to specific combinations of electronic transitions between the ground 4f(7) state at the top of the valence band and excited 4f(6)5d(1) states of Eu(2+) ions, which form the lowest energy conduction band. Temperature, magnetic field, and rotational anisotropy studies allowed us to distinguish crystallographic and magnetic-field-induced contributions to the THG. A strong modification of THG intensity for the 2.4 eV band and suppression of the THG for the 3.15 eV band was observed in applied magnetic field. Two main features of the THG spectra were assigned to 5d(t(2g)) and 5d(e(g)) subbands at 2.4 eV and 3.15 eV, respectively. A microscopic quantum-mechanical model of the THG response was developed and its conclusions are in qualitative agreement with the experimental results. (AU) | |
| Processo FAPESP: | 08/09753-3 - Detecção e controle óptico do magnetismo em semicondutores magnéticos e quantum dots |
| Beneficiário: | Andre Bohomoletz Henriques |
| Modalidade de apoio: | Auxílio à Pesquisa - Regular |