Fig. 1: Magneto-infrared spectroscopy of LaAlSi.
a Single-crystal X-ray diffraction pattern, identifying the (001) plane of LaAlSi. Inset: body-centered tetragonal structure of LaAlSi. b Raman spectrum of single crystal LaAlSi. c, d Stacked plots of relative magneto-reflectivity \({R}_{B}/{R}_{0}\) spectra measured in Faraday (\({{\bf{B}}}\parallel z\)) and Voigt (\({{\bf{B}}}\parallel y\)) geometries, respectively, with the infrared (IR) beam focused on the (001) plane. Three series of peak features, denoted by T0, T1, and T2, appear and evolve with the increasing magnetic fields, which are traced by red, green, and grey curves, respectively. Insets: schematic plots of magneto-optical geometries and cyclotron planes (red circle).
