By using density functional theory, we have studied vibrational features, Raman activities, and electronic properties of ultrathin hydrogen-passivated diamond nanowires (H-DNWs). Confinement imposes the softening of transverse acoustic modes and the hardening of the low-optical modes. Higher frequencies optical modes are more influenced by the surface termination effect. Surface effect splits transverse (TO) and longitudinal (LO) optical modes with a redshift from the bulk diamond. Electronic inspection shows that the surface terminated hydrogen atoms have the main contribution to the conduction bands of H-DNWs. This causes, contrary to our expectations from the quantum confinement effect, the electronic bandgap of H-DNWs becomes smaller than bulk diamond.
@article{arxiv.2009.02115,
title = {Phononic and electronic features of diamond nanowires},
author = {Farah Marsusi and Seyed Mostafa Monavari},
journal= {arXiv preprint arXiv:2009.02115},
year = {2020}
}