Crystal Growth and basic transport and magnetic properties of MnBi2Te4.

We report successful growth of magnetic topological insulator (MTI) MnBi2Te4. Depending, upon the heating schedule the phase formation in terms of various Bi2Te3 + MnTe structures viz. MnBi2Te4, MnBi4Te7, MnBi6Te10 and MnTe are seen in powder X-ray diffraction of crushed resultant crystals. The heating schedule basically deals with growth of the crystal from melt at 900C and very slow cooling (1C/hr) to around 600C with 24 hours hold time, followed by cooling to room temperature. Our detailed, PXRD Reitveld analysis showed that the resultant crystal is dominated by MnBi4Te7, MnBi6Te10 phases along with some MnTe content. The transport measurements showed a step like behavior at around 150K followed by cusp like structure in resistivity at around 20K due reported anti-ferromagnetic ordering of Mn. Both the resistivity transitions are seen clearly in dR/dT measurements at 150K and 20K respectively. The 20Ktransition of the compound is also seen in magnetic susceptibility. The studied MnBi2Te4 MTI crystal could be a possible candidate for Quantum Anomalous Hall (QAH) effect.