Under the framework of this project we theoretically investigated exciton states in strained GaN/AlN quantum dots with wurtzite (WZ) and zincblende (ZB) crystal structure. We show that strain field significantly modifies conduction and valence band edges of GaN/AlN quantum dots. Piezoelectric field is found to govern excitonic properties of WZ GaN/AlN quantum dots while it has very little effect on ZB GaN/AlN quantum dots. As a result, the exciton ground state energy in WZ GaN/AlN quantum dots with heights larger than 3 nm exhibits a red shift with respect to bulk WZ GaN energy gap. Obtained results are in good agreement with available experimental data and can be used to optimize GaN/AlN quantum dot parameters for proposed optoelectronic applications.



Relevant Publications:

* V.A. Fonoberov and A.A. Balandin, “Excitonic properties of strained wurtzite and zincblende GaN/AlN quantum dots,“ J. Applied Physics,94 : 7178 (2003)
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* V.A. Fonoberov, E.P. Pokatilov, and A.A. Balandin, “Interplay of confinement, strain, and piezoelectric effects in the optical spectrum of GaN quantum dots,“ J. Nanoscience and Nanotechnology, 3: 253, (2003)
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