A polariton laser is a new concept of device based on the Bose Einstein condensation of cavity exciton-polaritons. It offers intrinsically high modulation speeds, low thresholds, long lifetime and low power consumption. Polariton lasing has been demonstrated at low and room temperature in optically pumped structures. Electrical injection of excitons and polaritons states have been reported for GaAs structures, while the realization of an electrically driven polariton laser is still missing. The aim of the work presented in this thesis has been the modelling, design and optimization of GaN based devices, with regard to the aspects involved in the realization of the electrical injected polariton laser. To achieve these goals, a new simulation software has been developed to study the exciton transport in semiconductors and used together with conventional tools. Several simulations have been performed to understand the behaviour of GaN based light emitting diodes (LED), Vertical Cavity Vertical-cavity surface-emitting laser (VCSEL) and Polariton laser (PLASER) structures and new designs of GaN based devices have been proposed in order to optimize the electrical injection in GaN-based VCSELs/PLASERs and to achieve the polariton lasing in these structures. The strong interplay between carrier mobility, focussing efficiency and electrical injection has been carried for the first time. The results of this work have received dissemination through 4 publications in international journals, presentations and posters at international conferences, and a patent concerning a new design for electrical injection in GaN based VCSELs/PLASERs. This work has been developed within the European Project StimScat (STIMulated SCATtering) started the 1st of September 2005 and ended the 1st of September 2008. The aim of the project was the realization of two new forms of opto-electronic device, namely the polariton laser and polariton-based micron-size optical parametric amplifier, both operating at room temperature.
Petrolati, E. (2009). Study and optimization of polariton LASERs.
|Titolo:||Study and optimization of polariton LASERs|
|Data di pubblicazione:||4-set-2009|
|Anno Accademico:||A.A. 2007/2008|
|Corso di dottorato:||INGEGNERIA DEI SISTEMI SENSORIALI E DI APPRENDIMENTO|
|Settore Scientifico Disciplinare:||Settore ING-INF/01 - Elettronica|
|Tipologia:||Tesi di dottorato|
|Citazione:||Petrolati, E. (2009). Study and optimization of polariton LASERs.|
|Appare nelle tipologie:||07 - Tesi di dottorato|