Magnetic properties of thulium aluminoboride Tm Al B 4

Magnetic properties of thulium aluminoboride Tm Al B 4 were investigated. Strong anisotropic behavior is observed with the c axis indicated to be the easy axis. The Curie-Weiss temperatures showed a very large anisotropy with θ p || = − 5.3 K and θ p ⊥ = − 62 K . χ || c exhibits a drop around T N = 5.8 K indicating an antiferromagnetic transition. Magnetic transitions have not been observed for any of the other known aluminoboride phases. Successive sharp metamagnetic transitions were also observed at H C 1 = 11 kG and H C 2 = 24.5 kG with H || c . The magnetic behavior has interesting similarities to the well known RE B 4 system with possible multiple transitions occurring below T N , but the ordering behavior may be even more complex.