Carrier Transport in Heterojunction Nanocrystals Under Strain

TL;DR

This paper develops a theoretical model for carrier transport in strained heterojunction nanocrystals, highlighting how interface strain influences charge separation, bound states, and photocurrent behavior in nanoscale semiconductor heterostructures.

Contribution

It introduces an exactly solvable model for strained heterostructure interfaces, analyzing their impact on charge transport and bound states, with application to CdS/ZnSe systems.

Findings

Interface acts as a scattering potential facilitating charge separation.

Bound interfacial states influence carrier transport.

Calculated photocurrents and conductances including non-linear effects.

Abstract

We present a theory for carrier transport in semiconducting nanoscale heterostructures that emphasizes the effects of strain at the interface between two different crystal structures. An exactly solvable model shows that the interface region, or junction, acts as a scattering potential that facilitates charge separation but also supports bound interfacial states. As a case study, we model a Type-II CdS/ZnSe heterostructure. After advancing a theory similar to that employed in model molecular conductance calculations, we calculate the electron and hole photocurrents and conductances, including non-linear effects, through the junction at steady-state.