Absorption and birefringence of short period superlattices waveguides

✍ Scribed by V. Voliotis; R. Grousson; P. Lavallard; M.L. Roblin; R. Planel

• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 189 KB
• Volume: 13
• Category: Article
• ISSN: 0749-6036
• DOI: 10.1006/spmi.1993.1041

✦ Synopsis

The transmission of optical planar waveguides made of (\mathrm{GaAs} / \mathrm{Al} A) s short period superlattices is studied. The complete characterization of the waveguides makes possible the determination of the excitonic absorption of an enlarged quantum well embedded in the guiding structure. The absolute absorption coefficient is measured. We determine the binding energies, oscillator strengths and effective masses of excitons in (\mathrm{GaAs}) quantum wells surrounded by a GaAs/AlAs superlattice or a (\mathrm{Ga}{0.7} \mathrm{Al}{0.3} \mathrm{As}) alloy. We discuss the agreement with theoretical models. We also present new experimental results, obtained on the measurement of the weak absorption due to (\mathrm{a} \Gamma-\mathrm{X}_{\mathrm{z}}) transition in a type-II GaAs/AlAs superlatice.