CdSnAs₂ and InAs crystals at hydrostatic pressure up to 9 GPa

Abstract

The dependencies of resistivity ρ and Hall coefficient R _H on hydrostatic pressure up to 9 GPa have been investigated for the two semiconductor materials: CdSnAs₂ and InAs. The series of CdSnAs₂ samples has n∼ 10¹⁶ cm⁻³ (for those doped with Cu) and n∼ 10¹⁸ cm⁻³ (for undoped) of electron concentration. The InAs undoped sample has n∼ 10¹⁶ cm⁻³. For all CdSnAs₂ samples, a polymorphous phase transition takes place at P∼ 4.2 GPa. This transition is accompanied with the decomposition of initial compound. In InAs, the polymorphous phase transition is reversible: after decompression the initial composition is the same. The analysis of ρ (P) in both CdSnAs₂ and InAs, points out on the existence of quasi-localized energy levels deep in conduction band.

Keywords:

• Quasi-localized energy level
• Bridgman anvil
• Hydrostatic pressure
• Polymorphous phase transition

Acknowledgements

The work is carried out under the financial support of Russian foundation for basic research (Projects: No. 05-02-16608) and project of RAS Presidium ‘Physics and mechanics of highly condensed matter and of the problem of inner structure of the Earth and planets’.