Interface relaxation and band gap shift in epitaxial layers

Although it is well known that the interface relaxation plays the crucial role for the electronic properties in semiconductor epitaxial layers, there is lack of a clear definition of relationship between interfacial bond-energy variation and interface bond-nature-factor (IBNF) in epitaxial layers before and after relaxation. Here we establish an analytical method to shed light on the relationship between the IBNF and the bond-energy change, as well as the relation with band offset in epitaxial layers from the perspective of atomic-bond-relaxation consideration and continuum mechanics. The theoretical predictions are consistent with the available evidences, which provide an atomistic understanding on underlying mechanism of interface effect in epitaxial nanostructures. Thus, it will be helpful for opening up to tailor physical-chemical properties of the epitaxial nanostructures to the desired specifications.