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Single crystals of LnRu2Ga8 and LnCo2Al8 (Ln = La and Pr) were grown using a Ga/Al self-flux method. An orthorhombic CaCo2Al8-type structure with space group Pbam (No.55) of them was identified by x-ray diffraction. LaRu2Ga8 and LaCo2Al8 are Pauli paramagnetic down to 2 K, while PrRu2Ga8 and PrCo2Al8 show antiferromagnetic (AFM) order at 2.5 and 5 K, respectively. Strong magnetic anisotropy in PrRu2Ga8 and PrCo2Al8 single crystals was found by an anisotropic magnetic measurement. The field-induced FM state was observed in both PrRu2Ga8 and PrCo2Al8 for H||c. However, in the case of H⊥c, the AFM state is robust. The strong magnetic anisotropy in PrRu2Ga8 FM and PrCo2Al8 is due to their anisotropic magnetic interactions that FM interactions are dominant in the case of H||c while AFM interactions for H⊥c.

Dimensionality reduction induced metal-insulator transitions in oxide heterostructures are usually coupled with structural and magnetic phase transitions, which complicate the interpretation of the underlying physics. Therefore, achieving isostructural MIT is of great importance for fundamental physics and even more for applications. Here, we report an isostructural metal-insulator transition driven by dimensional-crossover in spin-orbital coupled SrIrO3 films. By using in-situ pulsed laser deposition and angle-resolved photoemission spectroscopy, we synthesized and investigated the electronic structure of SrIrO3 ultrathin films with atomic-layer precision. Through inserting orthorhombic CaTiO3 buffer layers, we demonstrate that the crystal structure of SrIrO3 films remains bulk-like with similar oxygen octahedra rotation and tilting when approaching the ultrathin limit. We observe that a dimensional-crossover metal-insulator transition occurs in isostructural SrIrO3 films. Intriguingly, we find the bandwidth of Jeff=3/2 states reduces with lowering the dimensionality and drives the metal-insulator transition. Our results establish a bandwidth controlled metal-insulator transition in the isostructural SrIrO3 thin films.