Institute of Industrial Science, University of Tokyo, Tokyo 153-8505, Japan.
Phys Rev Lett. 2010 Aug 13;105(7):077402. doi: 10.1103/PhysRevLett.105.077402. Epub 2010 Aug 11.
Coherent spin oscillations were nonthermally induced by circularly polarized pulses in the fully compensated antiferromagnet NiO. This effect is attributed to the action of the effective magnetic field generated by an inverse Faraday effect on the spins. The novelty of this mechanism is that spin oscillations are driven by the time derivative of the effective magnetic field which acts even on "pure" antiferromagnets with zero net magnetic moment in the ground state. The measured frequencies (1.07 THz and 140 GHz) correspond to the out-of-plane and in-plane modes of antiferromagnetic spin oscillations.
圆偏振脉冲在完全补偿的反铁磁体 NiO 中非热诱导出相干自旋振荡。这种效应归因于反法拉第效应产生的有效磁场对自旋的作用。该机制的新颖之处在于，自旋振荡是由有效磁场的时间导数驱动的，即使在基态净磁矩为零的“纯”反铁磁体中，该磁场也会起作用。测量到的频率（1.07 THz 和 140 GHz）对应于反铁磁自旋振荡的面外和面内模式。
