Properties of an Optimized Fe/Pt-based Spintronic Terahertz Emitter: Excitation Power and Wavelength Dependences

A spintronic bilayer structure of 2-nm Fe and 3-nm Pt grown by molecular beam epitaxy on MgO substrate was evaluated as a viable THz radiation source for different excitation wavelengths and various average pump power levels. We demonstrate that this optimized Fe/Pt structure is an efficient THz emitter for 800-nm and 1550-nm pump wavelengths even with low excitation power.