Magnetic phase transitions and linear magnetic dichroism in manganese-doped copper metaborate (Cu,Mn)B2O4
The work presents a study of manganese-doped copper metaborate (Cu, Mn) B2O4 using optical spectroscopy. The temperature of the antiferromagnetic phase transition T-N = 19 K has been defined according to the absorption spectra. Polarization studies (Cu, Mn) B2O4 in isotropic ab-plane show the presence of linear antiferromagnetic dichroism in the magnetically ordered state previously observed in pure copper metaborate CuB2O4. This measurement allows to find the magnetic phase transition into an elliptical structure at the temperature T* = 7.0 K.