Evidence of lateral electric fields in c -plane III-V nitrides via terahertz emission

We observe terahertz (THz) emission from c -plane InN and In0.15Ga0.85N films on GaN templates due to surface-normal transport with a strong anomalous in-plane transport component. Analysis of the rotational dependence of the THz emission associated with this in-plane transport indicates that an electric field exists along the [1-100] m-axis correlated with the underlying template miscut. Calculations show that the field is correlated with strain-induced polarization fields at the heterointerface related to step-like charges at interfaces of the epilayers and the miscut templates. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)