Phonon dispersion and Raman spectra of wurtzite InAs under pressure

• First principles lattice dynamics calculations are performed for InAs in WZ phase.
• Calculated high pressure Raman spectra is compared with recent InAs nanowire experiments.
• Possible phase transition is indicated at 10 GPa due to disappearance of LO peak and unstable phonon modes.
• Mechanical and thermodynamical properties are calculated in WZ phase.
• Pressure variations of LO–TO frequencies and Born effective charges are reported.

The authors have systematically studied the vibrational properties of wurtzite InAs at high pressure within the Density Functional Theory scheme. It is found that pressure significantly affects the phonon dispersion curves and Raman spectra. We observed an indication of phase transition for WZ-InAs at about 10 GPa. The elastic constants calculation show mechanical stability for WZ-InAs. The calculated values of structural parameters are in good agreement with available data. There is a quadratic increase in optical modes with pressure while the LO–TO splitting and effective charge decrease linearly with pressure.