Stochastic analysis of charging and recombination in double-hetero tunnel-junction quantum dot semiconductor laser

The double-hetero tunnel-junction quantum dot semiconductor laser model is presented in this paper to analyze a charging process by tunneling to an isolated quantum dot in an active area. The double-hetero tunnel junction structure including a small band gap quantum dot prevents tunneling transitions of electrons and holes to p and n type side areas and enhances the recombination in the dots, while a high band gap quantum dot can be used for an electron or hole current selectable transistor. A photon contained in a laser output is produced by a recombination of an electron and a hole in the quantum dot. Although the output contains many photon quanta, each charging of the electron and hole is discreet process, and the recombination is occurred in a probability manner. The laser output analysis is based on the stochastic process analysis appropriate to the treatment of the problem. The analytical solution for the probability to the charging number is given, and numerical computations of the output characteristics are presented.