We report some results on the analysis of thermo-electromechanical effects in low dimensional semiconductor
nanostructures (LDSNs). A coupled model of thermoelectroelasticity has been applied to the analysis of quantum dots
and quantum wires. Finite element solutions have been obtained for different thermal loadings and their effects on the
electromechanical properties in quantum dots and quantum wires are presented. Our model accounts for a practically
important range of internal and external thermoelectromechanical loadings. Results are obtained for typical quantum
dot and quantum wire systems with cylindrical geometry. The comparative analysis of thermoelectromechanical
effects in quantum dots and quantum wires is also presented. It is observed that the electromechanical effects in
LDSNs are noticeably influenced by thermal loadings. The influence is more significant in quantum dots as compared
to that of quantum wires.
We quantify the influence of thermopiezoelectric effects in nano-sized Al<sub>x</sub>Ga<sub>1-x</sub>N/GaN heterostructures for pressure
sensor applications based on the barrier height modulation principle. We use a fully coupled thermoelectromechanical
formulation, consisting of balance equations for heat transfer, electrostatics and mechanical field.
To estimate the vertical transport current in the heterostructures, we have developed a multi-physics model
incorporating thermionic emission, thermionic field emission, and tunneling as the current transport mechanisms.
A wide range of thermal (0-300 K) and pressure (0-10 GPa) loadings has been considered. The results
for the thermopiezoelectric modulation of the barrier height in these heterostructures have been obtained and
optimized. The calculated current shows a linear decrease with increasing pressure. The linearity in pressure
response suggests that Al<sub>x</sub>Ga<sub>1-x</sub>N/GaN heterostructure-based devices are promising candidates for pressure
sensor applications under severe environmental conditions.