Investigation of Sample Dependence in α-RuCl₃ Crystals

α-RuCl₃ is a strong candidate for the realization of Kitaev’s honeycomb model, whose ground state is a quantum spin liquid with Majorana fermions. Many studies have been carried out on α-RuCl₃ and some results have been explained by the fractionalized particle picture. However, many experimental results are still controversial due to the strong sample dependence of α-RuCl₃. To investigate the sample dependence in α-RuCl3, various α-RuCl3 crystals grown using chemical vapour transport method with different conditions were characterized. Two types of crystals were grown: thick crystals and thin crystals. We found that thick crystals exhibit consistent x-ray diffraction pattern, magnetization response, and specific heat. On the other hand, strong sample dependence was found in the characterization data of the thin crystals. This work addresses the sample dependence in α-RuCl₃ by providing a way to synthesize high-quality crystals with consistent physical properties and criteria to distinguish them from low-quality crystals.