Ultrafast all-optical magnetic switching in NaTb(WO4)2

The operation of an all-optical magnetic switching based on the paramagnetic NaTb(WO4)2 crystals is carried out by the time-resolved magneto-optical Faraday effect. Our results demonstrate that the switching time can be as fast as ∼500 fs at room temperature. The switching amplitude shows a linear dependence on the excitation intensity, which is proportional to the magnetization induced by the circularly polarized light. Based on the inverse Faraday effect in magneto-optical crystal, the switching mechanisms arising from circular dichroism and birefringence are discussed. By tailoring the magneto-optical properties of NaTb(WO4)2 crystal, the switching magnitude can be modulated.