Absorption spectroscopy and band structure in polarized GaN/AlxGa1-xN quantum wells

Citation
C. Wetzel et al., Absorption spectroscopy and band structure in polarized GaN/AlxGa1-xN quantum wells, PHYS ST S-A, 183(1), 2001, pp. 51-60
Citations number
26
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
PHYSICA STATUS SOLIDI A-APPLIED RESEARCH
ISSN journal
00318965 → ACNP
Volume
183
Issue
1
Year of publication
2001
Pages
51 - 60
Database
ISI
SICI code
0031-8965(200101)183:1<51:ASABSI>2.0.ZU;2-T
Abstract
The absorption properties in hetero-polarization GaN/AlxGa1-xN (x = 0.06) q uantum well structures are studied in reflection, photoreflection, and phot oluminescence excitation spectroscopy and compared with the results of band structure calculations. Above the energy of the main luminescence transiti ons we observe three distinct absorption thresholds. From Franz-Keldysh osc illations in the absorption spectra we directly derive the value of the act ing electric field within the barriers. Upon this field strength we base a calculation of the electronic band structure and interband transition energ ies. The results suggest that the observed absorption edges are the AlGaN b and edge and two quantized levels involving the crystal-field spilt-off hol e.