Theory of Exciton-Polaritonic Absorption in Multiple Quantum Wells

✍ Scribed by V. A. Kosobukin

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 258 KB
• Volume: 208
• Category: Article
• ISSN: 0370-1972
• DOI: 10.1002/(sici)1521-3951(199807)208:1<271::aid-pssb271>3.0.co;2-v

✦ Synopsis

A theory is presented for electromagnetic energy transfer and absorption mediated by quasi-twodimensional excitons in regular multiple-quantum-well (MQW) structures. The absorptivity, absorption coefficient and their integrals over the photon frequency are generally expressed as functions of the ratio between the excitonic non-radiative and radiative damping rates. The dependences of the integral absorption characteristics on the non-radiative damping rate G of an exciton are found to decrease at small G, so do at low temperatures the dependences on temperature due to phonon-assisted decay of the exciton. Such behaviour of integral absorption versus the non-radiative damping rate is ascribed to the specific role of radiative exciton decay to be accompanied by photon escape from a finite-length MQW structure. That manifests itself as a violation of the Bouguer law at weak non-radiative damping or low temperatures.