Superconductor-insulator transition in fcc-GeSb2Te4 at elevated pressures

Abstract

We show that polycrystalline GeSb2Te4 in the fcc phase (f-GST), which is an insulator at low temperature at ambient pressure, becomes a superconductor at elevated pressures. Our study of the superconductor to insulator transition versus pressure at low temperatures reveals a second order quantum phase transition with linear scaling (critical exponent close to unity) of the transition temperature with the pressure above the critical zero-temperature pressure. In addition, we demonstrate that at higher pressures the f-GST goes through a structural phase transition via amorphization to bcc GST (b-GST), which also become superconducting. We also find that the pressure regime where an inhomogeneous mixture of amorphous and b-GST exists, there is an anomalous peak in magnetoresistance, and suggest an explanation for this anomaly.

arXiv comment9 pages, 7 figures

References in corpus (8)

• Granular Electronic Systems
• Coexistence of tetrahedral and octahedral-like sites in amorphous phase change materials
• Localized Superconductivity in the Quantum-Critical Region of the Disorder-Driven Superconductor-Insulator Transition in TiN Thin Films
• Superconductivity in the insulating phase above the field-tuned superconductor-insulator transition in disordered indium oxide films
• Weak antilocalization and disorder-enhanced electron interactions in crystalline GeSbTe
• Superconductivity on the localization threshold and magnetic-field-tuned superconductor-insulator transition in TiN films
• Theory of Magneto-resistance of Disordered Superconducting Films
• Superconductivity in multiple phases of compressed GeSb2Te4

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