Devki Talwar published a research article titled “Atypical phonon modes in zinc-blende BN/GaN superlattices” in Applied Physics Letters 102, 252101 (2013).
Comprehensive results of the atomic vibrations are reported in unconventional short-period zb BN/GaN superlattices (SLs) by exploiting a rigid-ion-model and taking into account both the short-range and long-range Coulomb interactions. Besides the anisotropic mode behavior of optical phonons, our study provided evidence of acoustic-mode anti-crossing, mini-gap formation, confinement, as well as BN-like modes falling within the gap that separates optical phonon bands of the two materials. Controlling the vibrational spectrum by altering SL-period can create excellent opportunities for improving the electrical and thermal properties of SL-based III-N devices.
Department of Physics