Photoemission study of MnBi and GdNi2Ge2
Photoelectron spectroscopy was performed on single crystals of MnBi and GdNi2Ge2 utilizing synchrotron radiation as the light source. MnBi is known for its large magneto-optical Kerr rotation and GdNi 2Ge2 is studied for its intriguing magnetic properties at low temperature, including a spin density wave (SDW) that is reported to occur at 27.1 K. Angle resolved photoemission was used to investigate the electronic band structures of both materials. Resonant photoemission was used to characterize valence band features. The shallow core levels were also investigated using angle integrated photoemission. Results from MnBi measurements are compared with recent theoretical bandstructure and density of states calculations. GdNi2Ge2 results are compared to the theoretical band structure calculations. They support theoretical handling of the Gd-4f levels as being part of the atomic core. The search for the SDW was inconclusive.