Artigo
Coherent properties and Rabi oscillations in two-level donor systems
Fecha
2006-06-01Registro en:
Brazilian Journal of Physics. São Paulo: Sociedade Brasileira Fisica, v. 36, n. 2A, p. 419-422, 2006.
0103-9733
10.1590/S0103-97332006000300050
S0103-97332006000300050
WOS:000238575800050
2-s2.0-33746062454
WOS000238575800050.pdf
1023310738730000
Autor
Universidade Federal Fluminense (UFF)
Univ Estadual Feira Santana
Universidade Estadual Paulista (Unesp)
Universidade Estadual de Campinas (UNICAMP)
Universidade Federal do Rio de Janeiro (UFRJ)
Resumen
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.