Broadband terahertz emission from FeCrAl alloy films deposited by magnetron sputtering technology

Recently, terahertz (THz) emission from ferromagnetic materials has aroused significant scientific interest. Our interest is in the interactions between FeCrAl alloy films and THz emission characteristics. Preference-orientation (110) FeCrAl alloy films with different element percentage of Fe, Cr, Al were fabricated by magnetron sputtering technology. The corresponding magnetization and the THz emission characteristics were studied by vibrating sample magnetometer (VSM) and Fourier Transform Spectrometer. The results showed that for the first time broadband THz spectra in the frequency range of 2 THz to 15 THz from the FeCrAl alloy films excited by a direct current power have been emitted. The THz radiation intensity was determined by the magnetization and the electric current. The broadband THz emission from FeCrAl alloy films, which can be due to the thermal demagnetization and the surface second-order nonlinear optical effects were discussed.