2011/03/13 by Yasemin Şengün, Sondan Durukanoğlu
Physics and Astronomy · #Atom (system on chip) #Condensed matter physics #Density of states #Materials science #Molecular physics #Molecular vibration #Nanotechnology #Nanowire #Optics #Phonon #Physics #Quantum and electron transport phenomena #Raman spectroscopy #Semiconductor materials and interfaces #Surface and Thin Film Phenomena #cond-mat.mtrl-sci #cond-mat.other
paper · pdf · doi:10.1103/physrevb.83.113409
arxiv created 2011/03/13 · openalex publication_date 2011/03/31 · arxiv updated 2015/05/27 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We investigated the vibrational density of states (VDOS) of a thin Cu nanowire with \ensuremath⟨100\ensuremath⟩ axial orientation and considered the effect of axial strain. The VDOS were calculated using a real-space Green's function approach with the force-constant matrices extracted from the interaction potential based on the embedded atom method. The VDOS of a strain-free nanowire showed quite distinctive characteristics compared to that of a bulk atom, the most striking feature of which was the existence of high-frequency modes above the top of the bulk phonon spectrum. We further predicted that the low-frequency characteristics of the VDOS would reveal quasi-one-dimensional behavior only when the wire was extremely thin. Through decomposition of VDOS into local atoms, we also exhibited that while the anomalous increase in the low-frequency density of states was mainly due to the corner atoms, the enhancement in high-frequency modes was primarily moderated by core atoms. Additionally, we found that the high-frequency band above the top of the bulk phonon spectrum shifted to higher frequencies, whereas the characteristics at low frequencies remained almost the same upon stretching the nanowire along the axial direction.