Magneto-optical effects in semimetallic Bi1–xSbx (x=0.015)

We report the results of infrared and magneto-optical spectroscopy study on electrodynamic response of bismuth doped with 1.5% of antimony. The spectra are presented for temperatures down to 4.2 K, and in magnetic fields as high as 18 T. The results reveal strong magneto-optical activity, similar to pure bismuth, however there are some differences introduced by antimony doping. Analysis of optical functions reveals that the two type of charge carriers respond differently to external magnetic field. Finally, when the system enters the extreme quantum regime, both the inter- and intraband Landau Level transition are observed in the spectra.