Resonant photoionization absorption spectra of spherical quantum dots

Abstract

We study theoretically the mid-infrared photon absorption spectra due to bound–free transitions of electrons in individual spherical quantum dots. It is established that change of the dot size in one or two atomic layers or/and number of electrons by one or two can change the peak value of the absorption spectra in orders of magnitude and energy of absorbed photons by tens of millielectronvolts. The reason for this is the formation of specific free states, called resonance states. Numerical calculations are performed for quantum dots (QDs) with radius varying up to 200 Å, and one to eight electrons occupying the two lowest bound states. It is supposed that realistic QD systems with resonance states would be of much advantage to design novel infrared QD photo-detectors.

A study of an exciton in a quantum dot with Woods–Saxon potential

“…These features are useful for the development of optoelectronic devices with tunable emission or transmission properties and ultra-narrow spectral linewidths. Hence, optical properties of QDs have been investigated both experimentally and theoretically by many authors [2][3][4][5][6]. In the optical transition of quantum confined few-particle systems, the analysis of the exciton states is inevitable because the confinement of quasiparticles in such structure leads to the enhancement of the oscillator strength of electron-hole excitations.…”

Optical properties of impurity-bound polaron in a parabolic quantum dot

“…These features are useful for the development of optoelectronic devices with tunable emission (or transmission) properties and ultra-narrow spectral linewidths. Hence, the linear and nonlinear optical properties of QDs have been investigated both experimentally and theoretically by many authors [3][4][5][6][7][8].…”

Optical properties of an off-center hydrogenic impurity in a spherical quantum dot with Gaussian potential

“…These features are useful for the development of optoelectronic devices with tunable emission or transmission properties and ultra-narrow spectral linewidths. Hence, nonlinear optical properties of QDs have been investigated both experimentally and theoretically by many authors [6][7][8][9][10][11][12][13][14].…”