  Results of the first ab initio simulations of InN/GaN multiquantum well (MQW)
system are presented. The DFT results confirm the presence of the polarization
charge at InN/GaN interfaces, i.e. at polar InN/GaN heterostructures. These
results show the potential jumps which is related to the presence of dipole
layer at these interfaces. An electrostatic polarization analysis shows that
the energy minimum condition can be used to obtain the field in InN/GaN system,
employing standard polarization parameters. DFT results are in good agreement
with polarization data confirming the existence of electric field leading to
separation of electron and holes in QWs and emergence of Quantum Confined Stark
Effect (QCSE).
