arXiv, 2018
DOI: 10.48550/arxiv.1812.08560
American Chemical Society, Inorganic Chemistry, 10(58), p. 6659-6668, 2019
DOI: 10.1021/acs.inorgchem.8b03545
Fine-tuning chemistry by doping with transition metals enables new perspectives for exploring Kitaev physics on a two-dimensional (2D) honeycomb lattice of α-RuCl3, which is promising in the field of quantum information protection and quantum computation. The key parameters to vary by doping are both Heisenberg and Kitaev components of the nearest-neighbor exchange interaction between the Jeff = 1/2 Ru3+ spins, depending strongly on the peculiarities of the crystal structure. Here, we successfully grew single crystals of the solid solution series Ru1-xCrxCl3 with Cr3+ ions coupled to the Ru3+ Kitaev host using chemical vapour transport reaction. The Cr3+ substitution preserves the honeycomb type lattice of α-RuCl3 with mixed occupancy of Ru/Cr sites, no hints on cationic order within the layers were found by single crystal X-ray diffraction and transmission electron microscopy investigations. In contrast to the high quality single crystals of α-RuCl3 with ABAB ordered layers, the ternary compounds demonstrate a significant stacking disorder along the c-axis direction evidenced by X-ray diffraction and high resolution scanning transmission electron microscopy (HR-STEM). Raman spectra of substituted samples are in line with a symmetry conservation of the parent lattice upon chromium doping. At the same time, magnetic susceptibility data indicate that the Kitaev physics of α-RuCl3 is increasingly repressed by the dominant spin-only driven magnetism of Cr3+ in Ru1-xCrxCl3.