New advances in the light-emission theory. Novel effects in superlattice laser spectra

Física Teórica y Materia Condensada, UAM-Azcapotzalco - Av. S. Pablo 180, C.P. 02200, México D. F., México

Received: 31 March 2017
Accepted: 17 May 2017

Abstract

An important drawback of the standard theory, describing light-emitting periodic structures, is the lack of explicit knowledge of the initial and final states. In the new approach, based on the theory of finite periodic systems, the superlattice eigenvalues and eigenfunctions, are rigorously and explicitly determined. This approach provides the possibility of a truly quantum calculation of the optical response of periodic structures. New selection rules, tunable surface-energy-levels repulsion and interesting optical-spectra effects, related to intra-subband and surface states, are reported. Most of the actually observed transitions, “forbidden” for the standard approach, become allowed. The unexplained phenomenon of clustering of narrow peaks, observed in high-resolution blue-laser spectra by Nakamura et al., are now fully explained and faithfully reproduced. The higher accuracy of this approach and the feasibility to control the detachment of the surface energy levels are important improvements relevant to optical-physics and the technological and biomedical applications.