The Yb based triangular lattice delafossites AYbX2 (A = alkali metal, X = O, S, Se) have recently been studied as quantum spin liquid candidates. We report the synthesis of powders and single crystals of CuYbSe2 with a perfect triangular lattice of Yb3+ moments. Magnetic susceptibility and heat capacity measurements reveal no evidence of long-range magnetic ordering down to 1.8~K in spite of a significant antiferromagnetic exchange between Yb3+ moments, suggesting a frustrated magnetic system. Electrical resistivity measurements indicate insulating behavior, consistent with the localized nature of magnetic moments. Heat capacity reveals that CuYbSe2 can be treated as an effective spin S=1/2 triangular lattice antiferromagnet below ∼50~K. Magnetic susceptibility measurements on single crystals reveals weak magnetic anisotropy. These properties position CuYbSe2 as a promising candidate for a quantum spin liquid state and as a new platform for exploring exotic magnetic ground states in triangular lattice systems.
@article{arxiv.2509.17023,
title = {Magnetic Frustration in CuYbSe$_2$: an Yb-Based Triangular Lattice Selenide},
author = {Barkha Khattar and Anzar Ali and Masahiko Isobe and Yogesh Singh},
journal= {arXiv preprint arXiv:2509.17023},
year = {2025}
}