Freezing of spin correlated nanoclusters in a geometrically frustrated magnet

The effects of disorder on the geometrically frustrated magnet ${\mathrm{ZnCr}}_2{\mathrm{O}}_4$ are examined through magnetic susceptibility and inelastic neutron-scattering measurements on ${\mathrm{Zn}}_{1-x}^{2+}{\mathrm{Cd}}_x^{2+}{\mathrm{Cr}}_2{\mathrm{O}}_4.$ 3% Cd doping destroys the Neél order of the parent compound, replacing it with a frozen phase of spin-correlated nanoclusters. The local spin structure of these nanoclusters endures through the paramagnetic, spin-glass, and Néel phases of the material.