1.
Nanotechnology
; 25(46): 465704, 2014 Nov 21.
Artigo
em Inglês
| MEDLINE
| ID: mdl-25360514
RESUMO
The pressure-dependent phonon modes of InAs nanowires have been investigated by Raman spectroscopy under high pressure up to â¼58 GPa. X-ray diffraction measurements show that InAs nanowires at 21 GPa exhibit a phase transition from a wurtzite to an orthorhombic crystal structure, with a corresponding drastic change in the first-order Raman spectra. In the low-pressure regime, a linear increase in phonon frequencies is observed, whereas splitting between longitudinal and transversal optical phonon modes decreases as a function of applied pressure. The calculated mode Grüneisen parameters and Born's transverse effective charge indicate that the wurtzite InAs nanowires exhibit a more covalent nature under compression.