Band Gap Tunability in Semiconductor Nanocrystals by Strain: Size and Temperature Effect

We put forward a theoretical model to elucidate the impact of strain on the electronic band gap tunability of semiconductor nanocrystals both in self-equilibrium state and stimulated by thermal approach from the perspective of atomistic origin based on the recently developed relationship between bond length and bond energy. Theoretical analyses pointed out the band gaps are significantly modified with changing solid size and temperature due to the development of a large lattice strain and found that the strains originated from thermal approach and that in a self-equilibrium state play the competitive role for the band offsets. Agreement between our theoretical predictions and experimental observations and simulations provides a new insight into the physical understanding on the electronic and optical properties of semiconductor nanocrystals.