  Magnetic excitations in the triangular-lattice Heisenberg antiferromagnet
(TLHA) CuCrO2 were studied using single-crystal inelastic neutron scattering. A
diffusive quasielastic component that persisted without developing a
correlation length over a wide temperature range both below and above the
ordering temperature was observed. Furthermore, characteristic momentum
dependence was observed that was reproduced using minimum spin clusters. The
robust spin clusters contrast with conventional magnetic ordering and may be
universal in TLHAs.
