Field-tunable quantum disordered ground state in the triangular-lattice antiferromagnet NaYbO.

Antiferromagnetically coupled spins on an isotropic triangular lattice are the paradigm of frustrated quantum magnetism, but structurally ideal realizations are rare. Here, we investigate NaYbO, which hosts an ideal triangular lattice of effective moments with no inherent site disorder. No signatures of conventional magnetic order appear down to 50 mK, strongly suggesting a quantum spin liquid ground state.