Investigation of Polaron Properties in Semiconductors Quantum Dot Under the Influence of an Oscillating Electric Radiation

Abstract

In this paper, we investigate the influence of oscillating electric field radiation on the properties of a polaron in semiconductor quantum dot (SCQD). Using the Lee-Low-Pines-Huybrecht (LLPH) method, we derive the ground and first excited state energy of polaron. The superposition of these two energy states forms a two levels system (TLS) which is considered a quantum bit, allowing us to evaluate the probability density. The capacitance and the conductance of the SCQD are also investigated using the Drude model. Our results indicate that the electric field has pronounced effects on the properties of the polaron in SCQD. Some of these effects include, but are not limited to: (i) the variation of the probability density with respect to the x and y planar coordinates; (2i) the periodical modification of the probability density with electric field frequency, and its dependence on longitudinal optical (LO)-phonon coupling strength constant; (3i) both positive and negative values for the energy of the system, indicating the formation of free and couple polaronic entities. In particular, we found that the ground state energy of the polaron is predominant in gallium arsenide (GaAs) SCQD. Our results also suggest that oscillating electric field radiation leads to both coherent population transfer from the first excited to the ground states and to the scattering phenomenon. Therefore, investigating the interaction of an oscillating polaron-electric field (laser radiation) is especially relevant for gallium arsenide (GaAs).