Phase Equilibria of the MnTe-Sb2Te3 System and Synthesis of Novel Ternary Layered Compound – MnSb4Te7

E.N Orujlu,M.B Babanly,Z.S Aliev,I.R Amiraslanov

doi:10.15330/pcss.22.1.39-44

Abstract

By using Differential Thermal Analysis (DTA) and Powder X-ray Diffraction (PXRD) techniques, the phase diagram of the MnTe-Sb2Te3 system has been constructed for the first time in the entire composition range. The system features two ternary layered van der Waals (vdW) compounds. Apart from known MnSb2Te4, novel MnSb4Te7 which a structural analogous of the known MnBi4Te7 was found in the system. Crystal structure parameters of both compounds were determined by Rietveld refinement using the fundamental parameter approach. Both compounds were found to decompose via peritectic reactions and possess significant homogeneity ranges. The title system is also characterized by the existence of the wide solid solution field based on the starting Sb2Te3. The present results would be useful for the bulk single crystal growth of both compounds from the liquid phase via the determination of primary crystallization areas.

Highlights

VdW materials based on bismuth and antimony chalcogenides have received great interest thanks to the attractive combination of intriguing thermoelectric and topological insulator (Tl) properties [1,2,3,4]
Non-trivial band topology and complex structures of these materials allow for the realization of many novel topological phenomena, such as quantum Hall effect, quantum spin Hall effect, quantum anomalous Hall effect (QAHE), Majorana fermions, topological axion insulators, magnetoresistance switch effect, etc., which have huge potential for electronic, spintronic applications or other future technologies [5,6,7,8,9,10,11,12]
Glassy carbon crucibles were used to synthesize MnTe to prevent manganese reaction with quartz. Both binary compounds were analyzed by Differential Thermal Analysis (DTA) and Powder X-ray Diffraction (PXRD) to check the phase purity and results were close to the values reported in the literature [33,34,35,36,37]

Summary

Introduction

VdW materials based on bismuth and antimony chalcogenides have received great interest thanks to the attractive combination of intriguing thermoelectric and topological insulator (Tl) properties [1,2,3,4]. Layered heterostructures contain both magnetic and Tl layers succeed to integrate these seemingly incompatible characters [15, 16, 21], e.g., recently confirmed first intrinsic antiferromagnetic TI - MnBi2Te4 [22]. In this connection, other possible ternary compounds containing magnetic transition metals (M) –. The phase diagram of the MnTeSb2Te3 binary system is determined experimentally for the first time and crystal structure refinement of ternary compounds is presented.

Experimental details

Results and discussion

Conclusion