Superconductivity in bulk polycrystalline metastable phases of Sb2Te3 and Bi2Te3 quenched after high-pressure–high-temperature treatment

• Published in: Chemical physics letters Vol. 631-632; pp. 97 - 102
• Main Authors: Buga, S.G., Kulbachinskii, V.A., Kytin, V.G., Kytin, G.A., Kruglov, I.A., Lvova, N.A., Perov, N.S., Serebryanaya, N.R., Tarelkin, S.A., Blank, V.D.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.07.2015
• ISSN: 0009-2614; 1873-4448
• DOI: 10.1016/j.cplett.2015.04.056

•Using HPHT treatment we synthesized new m-Sb2Te3 and m-Bi2Te3 metastable phases.•Metastable Sb2Te3 and Bi2Te3 phases possess low-dimensional superconductivity.•The magnetic susceptibility and magnetoresistance indicate topological insulator state. We synthesized bulk polycrystalline samples of metastable phases of Sb2Te3 and Bi2Te3 topological insulators by rapid quenching after a high-pressure–high-temperature treatment at P=3.7–7.7GPa; T=873K and found superconducting transitions with TConset=2K and 6K, respectively. A low critical current value of about 2mA in the metastable Sb2Te3 phase and an absence of the detectable heat capacity effect at the superconducting transition indicated a low-dimensional character of superconductivity. A zero-field magnetic susceptibility cusp and linear positive magnetoresistance indicate a topological insulator state.