New developments for nitride unipolar devices at 1.3 1.5 μm wavelengths
Abstract
We present a systematic investigation of ultrathin single and coupled GaN/AlN quantum wells grown by molecular beam epitaxy for applications to unipolar devices. Narrow Lorentzian-shaped intersubband absorptions are demonstrated tunable at telecommunication wavelengths. The linewidth is as small as 40 meV which sets a new state-of-the-art. Simulation of the intersubband wavelength and comparison with measurements leads us to revise the value of the conduction band offset at the GaN/AlN interface (1.7 ± 0.05 eV). We also present the observation of strong electron state coupling between two GaN wells separated by an ultra-thin 2 monolayer thick AlN barrier. This study allows us to refine the potential description at the GaN/AlN interface at the atomic monolayer scale. Excellent agreement with measurements is achieved assuming a potential drop over 1 ML.
- Publication:
-
Superlattices and Microstructures
- Pub Date:
- October 2006
- DOI:
- 10.1016/j.spmi.2006.09.016
- Bibcode:
- 2006SuMi...40..412N