Synthesis and anisotropic magnetic properties of LiCrTe2 single crystals with a triangular-lattice antiferromagnetic structure

We report on the synthesis of LiCrTe₂ single crystals and on their anisotropic magnetic properties. We have obtained these single crystals by employing a Te/Li-flux synthesis method. We find LiCrTe₂ to crystallize in a TlCdS₂-type structure with cell parameters of a = 3.9512(5) Å and c = 6.6196(7) Å at T = 175 K. The content of lithium in these crystals was determined to be neary stoichiometric by means of neutron diffraction. We find a pronounced magnetic transition at T_N^ab = 144 K and T_N^c = 148 K, respectively. These transition temperatures are substantially higher than earlier reports on polycrystalline samples. We have performed neutron powder diffraction measurements that reveal that the long-range low-temperature magnetic structure of single crystalline LiCrTe₂ is an A-type antiferromagnetic structure. Our DFT calculations are in good agreement with these experimental observations. We find the system to be easy axis with moments oriented along the c-direction experimentally as well as in our calculations. Thereby, the magnetic Hamiltonian can be written as H = H_Heisenberg + ∑ _iK_c(S_i^z)² with K _c = -0.34 K (where |S^z| = 3/2). We find LiCrTe₂ to be highly anisotropic, with a pronounced metamagnetic transition for H ⊥ ab with a critical field of μH_MM(5 K) ≈ 2.5 T. Using detailed orientation-dependent magnetization measurements, we have determined the magnetic phase diagram of this material. Our findings suggest that LiCrTe₂ is a promising material for exploring the interplay between crystal structure and magnetism, and could have potential applications in spin-based 2D devices.