MIT physicists created a long-lasting magnetic state in a material, using only light. The results provide a new way to control and switch antiferromagnetic materials, which are of interest for their potential to advance information processing and memory chip technology., The discovery could yield an entirely new class of devices that use light instead of electricity for applications ranging from accelerators and microscopes to speedier on-chip communications., In a recent study published in the journal Nature, researchers at the Max Planck Institute for the Structure and Dynamics of Matter and MIT used terahertz light to control and switch an antiferromagnet into a new magnetic state., In an article published in Nature Photonics, a collaboration between the labs of Professor Tobias J. Kippenberg at EPFL and Professor Sunil A. Bhave at Purdue University showcases such a magnetic-free, electrically driven optical isolator that enables light routing on a chip., From the perspective of applied science, the precise control of a synthetic magnetic field demonstrated by Hafezi et al. 10 offers an unprecedented platform for controlling light in a silicon, .