Magnetic-Field-Tunable High-Resistivity State Strongly Coupled to Complex Magnetism in NdSb0.5Te1.5

NdSbTe is a magnetic topological semimetal in which nontrivial electronic states coexist with antiferromagnetic order, while variation in the Sb/Te composition substantially modifies its electronic and magnetic properties. Here, we investigate the temperature- and magnetic field-dependent electrical transport properties of NdSb0.5Te1.5. The electrical resistivity exhibits nonmetallic behavior below approximately 100 K and develops a pronounced high-resistivity state below 4 K, reaching more than three orders of magnitude above its room temperature value. Multiple characteristic anomalies emerge within the high-resistivity state and are systematically suppressed by magnetic fields. The characteristic temperatures and critical fields consistently define multiple transport regimes in the H-T phase diagram. Remarkably, a relatively weak magnetic field of approximately 0.5 T induces an abrupt and hysteretic transition between high and low resistivity states. These results demonstrate an exceptionally large field-tunable resistive response closely coupled to the magnetic state in NdSb0.5Te1.5.