Magnetic Properties of Antiferromagnetic GdAlO3

Abstract

Specific-heat and magnetic-susceptibility measurements on GdAlO3 show that it undergoes a transition to antiferromagnetism at 3.69°K. Magnetization measurements on a single crystal at temperatures down to 0.6°K in fields up to 70 kOe show that the ordered state is a simple two-sublattice structure with the orthorhombic b axis as the axis of alignment. The spin flop, exchange, and anisotropy fields have been found to be 11.2 kOe, 20 kOe to 25 kOe, and 2.3 kOe to 3.0 kOe, respectively. No parasitic ferromagnetism is observed. Optical absorption studies of Er3+ and Dy3+ in GdAlO3 observe the spin flop and confirm that in the ordered structure the distorted simple cubic lattice of Gd3+ ions divides into two sublattices with each ion surrounded by six nearest neighbors belonging to the opposite sublattice.

Thermochemistry of rare-earth aluminate and aluminosilicate glasses

“…While the clustering of rare-earth dopant ions restricts the use of silica-based glasses to doping level of 100 ppm [4], the recent development of glasses based on aluminum oxide provides a new family of glasses that can dissolve large amounts of rare-earth ions [5], Experimental investigations of glass formation and properties of amorphous rare-earth aluminate materials have focused primarily on the yttrium aluminate garnet composition (YAG: Y 3 Al 5 O 12 ) [6][7][8]. Crystalline perovskites (REAlO 3 , RE-= rare-earth) are promising materials for both ceramic microwave resonators and substrates for high temperature superconducting microwave devices [9] because of their optical and magnetic properties [10,11]. The relations among the thermodynamic, structural and physical properties of the rare-earth aluminate glasses and crystalline ceramics pose interesting theoretical and practical problems, and provide insights for more complex systems, such as RE 2 O 3 -Al 2 O 3 -SiO 2 .…”

Spin-flop and antiferromagnetic phases of the ferromagnetic half-twist ladder compounds Ba3Cu3In4O12and Ba3Cu3Sc4O12

“…The sublattice magnetization is a phenomenological macroscopic description that holds for arbitrary spin. Some of the best realizations [25] of SF transitions are in [31] MnCl 2 (H 2 O) 4 with the s = 5/2 Mn 2+ ion and in [32] GdAlO 3 with the s = 7/2 Gd 3+ ion. Both have FM exchange in 2D layers whose direct modelling is very difficult and weak AFM exchange between layers.…”

Hydrothermal synthesis and characterization of polycrystalline gadolinium aluminum perovskite (GdAlO3, GAP)

“…The rare earth aluminates are of considerable interest because of their optical and magnetic properties and technological applications [1][2][3]. Rare earth aluminates serve as neutron absorbers, flux suppressors and high temperature container materials.…”