Spin-glass-like behavior in ferromagnetic phase of CdCr2S4

•The heat capacity and magnetic properties of single crystalline CdCr2S4 is studied.•The low-temperature heat capacity indicates the existence of an unknown excitation.•Magnetic properties show spin-glass-like behaviors.

The ferromagnetic phase of spinel compound CdCr2S4 was investigated by measuring the heat capacity and magnetic properties. The low-temperature heat capacity data indicate the existence of an unusual excitation besides the ferromagnetic spin wave and phonon excitations. The additional excitation with a T-linear contribution would relate to a continuous excitation such appeared in the glass-like state. The magnetic properties also showed spin-glass-like behaviors. These results suggest that the short-range magnetic clusters of the Cr3+ ions grow to larger spin clusters at low temperature.