Nonlinear Light-Induced Attosecond Magnetization Dynamics in NonMagnetic Materials

Magnetism is one of the most fundamental physical phenomena in nature. It arises from internal spin degrees of freedom, and can create complex textures and phases of matter[1-3]. Over the past two decades, immense efforts were devoted towards understanding and manipulating magnetism on ultrafast timescales with femtosecond lasers[4,5]. Such manipulation for instance, could pave the way for novel memory devices. However, in all works up to now the fastest measured or predicted magnetic response was on the order of few femtoseconds[6,7], and it is not yet clear what the fundamental speed-limit is for magnetization dynamics. Moreover, a turn-on of magnetism has not been observed or predicted using linearly-polarized light; rather, linearly-polarized light has so far only been used for ultrafast demagnetization[8].