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arXiv · 1101.1646

Strain-driven light polarization switching in deep ultraviolet nitride emitters

T. K. Sharma·Doron Naveh·E. Towe
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Abstract

Residual strain plays a critical role in determining the crystalline quality of nitride epitaxial layers and in modifying their band structure; this often leads to several interesting physical phenomena. It is found, for example, that compressive strain in AlxGa1-xN layers grown on AlyGa1-yN (x<y) templates results in an anti-crossing of the valence bands at considerably much higher Al composition than expected. This happens even in the presence of large and negative crystal field splitting energy for AlxGa1-xN layers. A judicious magnitude of the compressive strain can support vertical light emission (out of the c-plane) from AlxGa1-xN quantum wells up to x\approx 0.80, which is desirable for the development of deep ultraviolet light-emitting diodes designed to operate below 250nm with transverse electric polarization characteristics.

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T. K. Sharma, Doron Naveh, E. Towe. 2011-01-09. Strain-driven light polarization switching in deep ultraviolet nitride emitters. https://doi.org/10.1103/physrevb.84.035305

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