Ultrafast spin manipulation in antiferromagnets by femtosecond pulses

反铁磁体的自旋旋进频率达到了THz量级，远高于铁磁体的旋进频率，表明了超快磁记录的可能性。在本研究中，我们利用圆极化脉冲在反铁磁NiO中进行了非热自旋操控的磁光泵浦探测实验。我们已经观察到的振荡频率为1.1太赫兹和140千兆赫，对应于反铁磁共振频率的NiO。这一结果被解释为逆法拉第效应诱导自旋振荡，这是由样品中的有效磁场通过圆偏振光触发的。

Spin precession frequency of antiferromagnets reaches THz order, far above that of ferromagnets, indicating possibility of ultrafast magnetic recording. In this research, we have performed magneto-optical pump-probe experiment for non-thermal spin manipulation by circularly polarized pulse in antiferromagnetic NiO. We have observed oscillations with frequencies of 1.1 THz and 140 GHz that correspond to antiferromagnetic resonance frequencies of NiO. This results was interpreted as the inverse Faraday effect inducing spin oscillations which was triggered by an effective magnetic field in a sample by circularly polarized light.