Linear and nonlinear optical absorption coefficients in GaAs/Ga1−xAlxAs concentric double quantum rings: Effects of hydrostatic pressure and aluminum concentration

Abstract

The linear and nonlinear intra-band optical absorption coefficients in GaAs/Ga 1 À x Al x As two-dimensional concentric double quantum rings are investigated. Taking into account the combined effects of hydrostatic pressure and aluminum concentration the energies of the ground ðn ¼ 1, l ¼ 0Þ and the first excited state ðn ¼ 2, l ¼ 1Þ have been found using the effective mass approximation and the transfer matrix formalism. The energies of these states and the corresponding threshold energy of the intraband optical transitions are examined as a function of hydrostatic pressure and aluminum concentration for different sizes of the structure. We also investigated the dependencies of the linear, nonlinear, and total optical absorption coefficients as functions of the incident photon energy for different values of hydrostatic pressure, aluminum concentration, sizes of the structure, and incident optical intensity. Its is found that the effects of the hydrostatic pressure and the aluminum concentration lead to a shifting of the resonant peaks of the intra-band optical spectrum.

Optical properties of poly[2-methoxy-5-(3′,7′-dimethyloctyloxy)-1,4-phenylenevinylene] light-emitting polymer solutions: effects of molarities and solvents

“…The nonlinear optical properties such as optical absorption [12][13][14] have shown high potential [15] for device applications in far-infrared laser amplifiers [16], photo-detectors [17], and high-speed electro-optical modulators [18]. The extinction coefficients, including mass extinction coefficient (α) and molar extinction coefficient (ε), are parameters to define the absorbance intensity at a given wavelength per mass density (g) or molar concentration (mol), respectively [19].…”

Donor Impurity-Related Optical Absorption in GaAs Elliptic-Shaped Quantum Dots

“…In Figure 2(c) we have also included the electronimpurity correlated energy for the ground state calculated via a variational technique and considering the 3D-shape of the structure (it means considering the 3D-character of the electron-impurity distance) [15][16][17]. Calculations were done with a one-variational parameter trial wave function.…”

Calculation of Zeeman splitting and Zeeman transition energies of spherical quantum dot in uniform magnetic field

“…In recent years, QDs have been extensively studied due to their potential applications in high performance devices. Therefore, a great deal of works have been performed on the electronic structures [2][3][4][5][6][7], binding energies [8][9][10][11], spin effects [12][13][14][15] and optical properties [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32] of QDs with different shape, size and the confinement potential by using various methods.…”