Quantum spin liquid ground state with the evidence of roton-like excitations at elevated temperatures in the triangular-lattice delafossite YbCuSe${}_2$

K. Bhattacharya, Y. Tokiwa, M. Majumder

We present a comprehensive experimental investigation of the temperature evolution of magnetic states in triangular-lattice delafossite YbCuSe${}_2$. Magnetization measurements on hi…