Theory of persistent, p-type, metallic conduction in c-GeTe

Abstract

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Coexistence of electron-glass phase and persistent photoconductivity in GeSbTe compounds

“…This is consistent with the p-type nature of GeSb x Te y , where the Fermi energy lies at the valenceband [39].…”

“…Recall that these materials are conducting by virtue of vacancies [39] and therefore we expect that mapping stoichiometry may be indicative of local carrier-concentration. This was done by employing energy-dispersive-spectroscopy (EDS) in the STEM mode at 200kV beam.…”

Structural and electrical properties of Germanium-doped Sb70Te30 eutectic thin films

“…These measurements show p-type conductivity and an increase in the carrier concentration with the increase in Ge. P-type conductivity is also observed in other crystalline chalcogenide materials such as Ge 2 Sb 2 Te 5 [22] and GeTe [23]. In these materials Ge and Sb vacancy determined carrier transport and lead to p-type metallic conduction [23].…”

Structural disorder in the high-temperature cubic phase of GeTe

“…36,48 To reveal the band gap of the perfect stoichiometric GeTe, the DFT-determined models with routine LDA/GGA functionals were intensively studied, showing various band gap between 0.4-0.7 eV. 49 Most of these calculations, however, still underestimate the band gap, particularly when DFT deals with the disordered or defective systems. To this end, we have applied GGA-1/4 method which promises to be more precise in determining the band gap of disordered GeTe (see Method section for details).…”