Raman study of magnetic phase transitions of hexagonal manganites

Results of Raman studies of magnetic phase transitions of hexagonal LuMnO 3 single crystal and HoMnO 3 thin films are compared directly with the results of magnetic measurements. Our results show that the temperature dependent Raman study of magnon scattering provides a simple and accurate method for investigating magnetic phase transitions, especially in HoMnO 3 thin films. In single crystal, our optical method provides results as good as magnetization measurements.