反铁磁DyFeO3单晶中自旋极化波的全太赫兹相干控制研究

Hz time domain spectroscopy (TDS) with picosecond temporal resolution is used to achieve the spin coherent control in an antiferromagnetic DyFeO3 single crystal. It is demonstrated that by adjusting the arriving time between the excitation and control THz pulse, the amplitude of the free induction decay (FID) signals emitted from the precession of the macroscopic magnetization at the frequency of quasiferromagnetic mode (FM, 0.38 THz) and quasiantiferromagnetic mode (AFM, 0.52 THz) can be coherently driven to large amplitude or switched off, respectively. Furthermore, when FM and AFM spin precession are launched simultaneously, an appropriately timed sequence of the double THz pulses can be used to select any spin mode. Our experimental results attest that all-THz coherent control is an efficient and ultrafast way to switch the spin precession in antiferromagnet nondestructively.