Time-Resolved X-Ray Ferromagnetic Resonance Method Based on Synchrotron Radiation

In combination with ferromagnetic resonance and magnetic circular dichroism, the time-resolved X-ray ferromagnetic resonance method based on synchrotron radiation devices, which adopts the "pump-probe" technique of phase shift mode, is a unique technique to study a wide class of spintronics issues such as spin transfer torque and spin current. In this paper, an experimental apparatus that allows for the combination of the picosecond time-resolved technique and X-ray ferromagnetic resonance is introduced for the first time at the third-generation synchrotron radiation light source in China, Shanghai Synchrotron Radiation Facility. With this apparatus, the single-layer Permalloy (Ni81Fe19, Py) undergoes ferromagnetic resonance under the 2. 5 GHz microwave excitation and we measure the time-dependent projection of electronic spin precession cone angle of Ni in the Ni81Fe19 film in the beam direction. The results show that the apparatus can excite the electronic spin precession of magnetic elements on the magnitude of 2. 5 GHz and detect the amplitude and phase of electronic spin precession on the picosecond scale. This apparatus can provide unique technical support for the investigation into the spintronic materials and devices.