High-magnetic-field-induced first-order magnetic transition and tricritical phenomenon in antiferromagnetic semimetal NdSb

The antiferromagnetic (AFM) semimetal NdSb is well-known for the interplay between exotic magnetism and topological properties, yet its magnetism remains inadequately clarified. In this study, we thoroughly investigate the magnetization of NdSb single crystals with high magnetic field (H) up to 30 T applied along various directions. We found that the AFM phase is suppressed by a magnetic field of 9.41 T when H//100 and 11.25 T when H//110, while the suppression field is from 9.41 T to 10.67 T with hysteresis of 1.26 T when H//111. The magnetization for H//100, the easy direction with typical magnetic transition, is studied in detail. The AFM phase for H//100 is suppressed toward lower temperatures by H, disappearing at approximately 6.25 K. Critical exponents β = 0:234(3), γ = 0:824(6), and δ = 4:90(6) are obtained for H//100, align with a tricritical mean-field model. The analysis of critical behavior suggests a field-induced tricritical phenomenon for H//100. An H - T phase diagram of the NdSb single crystal is constructed for H//100, revealing a field-induced first-order transition and identifying a tricritical point (TCP) at (T_tr = 6.25 K, H_tr = 9.41 T). The clarification of the multiple magnetic phases and transitions in NdSb provides crucial insights into understanding the correlation between its magnetism and topology.