Friday, April 3, 2015
Abstract-Terahertz magneto-optics in the ferromagnetic semiconductor HgCdCr2Se4
The response of the ferromagnetic HgCdCrSe at terahertz (THz) frequencies is studied using sensitive THz time-domain spectroscopy. It is shown that the state of broadband terahertz pulses, with a spectrum spanning from 0.2 THz to 2.2 THz, changes as an even function of the magnetization of the medium. Analysing the ellipticity and the rotation of the of the we show that these originate from linear and respectively, induced by the magnetic ordering. These are rather strong and reach 102 rad/m at an applied field of 1 kG which saturates the magnetization of the sample. Our observation serves as a proof-of-principle showing strong of the magnetic order on the response of a medium to at THz frequencies. These experiments also suggest the feasibility of spin-dependent transport on a sub-picosecond timescale.