Conductance Fluctuations and partially broken Spin Symmetries in Quantum Dots

We consider an electron-acoustic-phonon coupling mechanism associated with the dependence of crystal dielectric permittivity on the strain (the so-called Pekar mechanism) in nanostructures characterized by strong confining electric fields. The efficiency of Pekar coupling is a function of both the absolute value and the spatial distribution of the electric field. It is demonstrated that this mechanism exhibits a phonon wave-vector dependence similar to that of piezoelectricity and must be taken into account for electron transport calculations in nanostructures with extended field distributions. In particular, we analyze the role of Pekar coupling in energy relaxation in silicon inversion layers. Comparison with the recent experimental results is provided to illustrate its potential significance.