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

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.

Antisite-Defects Control of Magnetic Properties in MnSb2Te4

“…Due to Δ S mix , the compounds with Mn–Sb site mixing can be thermodynamically stabilized. Consequently, Mn–Sb antisite defects were commonly observed in MST, regardless of the growth method employed, including the solid-state reaction route, flux-growth method, chemical vapor transport method, and molecular beam epitaxy method. ,,,,,− ,,,− The Mn–Sb defects can be further controlled by the growth kinetics.…”

“…MST single crystals were grown by using the self-flux method. According to the reported phase diagram, a mixture of Mn pieces (99.999%), Sb grains (99.99%), and Te grains (99.999%) in a molar ratio of 1:6.7:11 (MnTe:Sb 2 Te 3 ≈ 1:3.35) was sealed in an evacuated quartz tube. The mixture was then heated from room temperature to 750 °C for 10 h and dwelled at 750 °C for 15 h. Subsequently, sample 1 (MST1) was obtained by using a designed cooling process (Figure a): first cooled from 750 °C to 635 °C for 2 h, then slowly cooled from 635 °C to 620 °C for 7.5 h, and finally quenched in ice water at 620 °C.…”

Recent progress in MnBi2nTe3n+1 intrinsic magnetic topological insulators: crystal growth, magnetism and chemical disorder

“…The three growth methods for MnBi 2 n Te 3 n +1 can all be generalized to their isostructural non-magnetic sister compounds (Sn, Pb) (Bi, Sb) 2 n Te 3 n +1 , and the chemically doped systems that exist continuously in between. In the flux growth of the Sb-doping series, since the melting point of Sb 2 Te 3 is ∼35 ○ higher than that of Bi 2 Te 3 [ 63 ], the decanting temperature must be correspondingly increased to be slightly higher than the melting point of (Bi 1− x Sb x ) 2 Te 3 , which increases with x . As a result, the optimal growth window is reduced.…”

3D ANALYTICAL MODELING OF CRYSTALLIZATION SURFACES OF THE MnTe–SnTe–Sb2Te3 SYSTEM

“…An analytical method was used for the 3D modeling of crystallization surfaces of the MnTe-SnTe-Sb 2 Te 3 system. The method was successfully tested in several works up to now [18][19][20][21][22][23]. The temperature dependences of the crystallization surface were determined as a form of function (1) for the three-component MnTe-SnTe-Sb 2 Te 3 system:…”