Details

Autor(en) / Beteiligte

• Abdul-Jabbar, N. M.
• Kalkan, B.
• Huang, G.-Y.
• MacDowell, A. A.
• Gronsky, R.
• Bourret-Courchesne, E. D.
• Wirth, B. D.

Titel

The role of stoichiometric vacancy periodicity in pressure-induced amorphization of the Ga2SeTe2 semiconductor alloy

Ist Teil von

• Applied physics letters, 2014-08, Vol.105 (5)

Ort / Verlag

Melville: American Institute of Physics

Erscheinungsjahr

2014

Quelle

AIP Journals Complete

Beschreibungen/Notizen

• We observe that pressure-induced amorphization of Ga2SeTe2 (a III-VI semiconductor) is directly influenced by the periodicity of its intrinsic defect structures. Specimens with periodic and semi-periodic two-dimensional vacancy structures become amorphous around 10–11 GPa in contrast to those with aperiodic structures, which amorphize around 7–8 GPa. The result is an instance of altering material phase-change properties via rearrangement of stoichiometric vacancies as opposed to adjusting their concentrations. Based on our experimental findings, we posit that periodic two-dimensional vacancy structures in Ga2SeTe2 provide an energetically preferred crystal lattice that is less prone to collapse under applied pressure. This is corroborated through first-principles electronic structure calculations, which demonstrate that the energy stability of III-VI structures under hydrostatic pressure is highly dependent on the configuration of intrinsic vacancies.