Relationship between Antisite Defects, Magnetism, and Band Topology in MnSb 2 Te 4 Crystals with T C ≈ 40 K.

MnSb 2 Te 4 has attracted extensive attention because of its rich and adjustable magnetic properties. Here, using a modified crystal growth method, ferrimagnetic MnSb 2 Te 4 crystals with enhanced Curie temperature ( T C ) of about 40 K with dominant hole-type carriers and intrinsic anomalous Hall effect is obtained. Time- and angle-resolved photoemission spectroscopy reveals that surface states are absent in both antiferromagnetic and ferrimagnetic MnSb 2 Te 4 , implying that they have topologically trivial electronic structures. We propose that the enhancement of ferrimagnetism mainly originates from the increase of intralayer magnetic coupling caused by the decrease of Sb content at Mn sites when the decrease of Mn concentration at Sb sites would prefer the nontrival band topology. Moreover, it is known that the initial saturation moment ( M is ) is sensitive to the concentrations of Mn/Sb antisite defects; thus, the M is could be a valuable parameter to evaluate the magnetic and topological properties of MnX 2 n Te 3 n +1 (X = Bi, Sb) families.