Coherent properties and rabi oscillations in two-level donor systems

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2014-02-26T17:25:21Z No. of bitstreams: 1 WOS000238575800050.pdf: 160330 bytes, checksum: 10f14bebba39a540b2177930d32d5295 (MD5) Made available in DSpace on 2014-02-26T17:25:21Z (GMT). No. of bitstreams: 1 WOS000238575800050.pdf: 160330 bytes, checksum: 10f14bebba39a540b2177930d32d5295 (MD5) Previous issue date: 2006-06-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:26:30Z No. of bitstreams: 1 WOS000238575800050.pdf: 160330 bytes, checksum: 10f14bebba39a540b2177930d32d5295 (MD5) Made available in DSpace on 2014-05-20T13:26:30Z (GMT). No. of bitstreams: 1 WOS000238575800050.pdf: 160330 bytes, checksum: 10f14bebba39a540b2177930d32d5295 (MD5) Previous issue date: 2006-06-01 Coherent properties and Rabi oscillations in two-level donor systems, under terahertz excitation, are theoretically investigated. Here we are concerned with donor states in bulk GaAs and GaAs-(Ga,Al)As quantum dots. We study confinement effects, in the presence of an applied magnetic field, on the electronic and on-center donor states in GaAs- (Ga,Al)As dots, as compared to the situation in bulk GaAs, and estimate some of the associated decay rate parameters. Using the optical Bloch equations with damping, we study the time evolution of the Is and 2p(+) states in the presence of an applied magnetic field and of a terahertz laser. We also discuss the role played by the distinct dephasing rates on the photocurrent and calculate the electric dipole transition moment. Results indicate that the Rabi oscillations are more robust as the total dephasing rate diminishes, corresponding to a favorable coherence time. Univ Fed Fluminense, Dept Fis, BR-24210340 Niteroi, RJ, Brazil Univ Estadual Feira Santana, Dept Fis, BR-44031460 Feira de Santana, BA, Brazil Univ Estadual Paulista, Fac Ciências, Dept Matemat, BR-17033360 Bauru, SP, Brazil Univ Estadual Campinas, Inst Fis, BR-13083970 Campinas, SP, Brazil Univ Fed Rio de Janeiro, Inst Fis, BR-21945970 Rio de Janeiro, Brazil Univ Estadual Paulista, Fac Ciências, Dept Matemat, BR-17033360 Bauru, SP, Brazil