Vasileios Balos, Genaro Bierhance, Martin Wolf, and Mohsen Sajadi:
Phys. Rev. Lett. 124 (9), 093201 (2020), pp.6;
Rotation of the plane of the polarization of light in the presence of a magnetic field, known as the Faraday rotation, is a consequence of the electromagnetic nature of light and has been utilized in many optical devices. Current efforts aim to realize the ultrafast Faraday rotation on a sub-picosecond time scale. To this end, the Faraday medium should allow an ultrafast process by which in the presence of an ultrashort intense magnetic field, the light polarization rotates. We meet the criteria by applying an intense single cycle THz mag-netic-field to simple molecular liquids and demonstrate the rotation of the plane of polarization of an optical pulse traversing the liquids on a sub-picosecond time scale. The effect is attributed to the de-flection of an optically induced instantaneous electric polarization under the influence the THz magnetic field. The resolved Faraday rotation scales linearly with the THz magnetic field and quadrati-cally with the molecular polarizability.
The original publication is available by link DOI: 10.1103/PhysRevLett.124.093201