Magnetism of rare earth borides - from frustration to fractional magnetisation plateaus

by Konrad Siemensmeyer, Helmholtz Zentrum Berlin

Friday 27 Nov 2009, 14:15 → 15:45 Europe/Berlin

Bldg. 25b, room 109

In this talk the magnetism of rare earth borides like RE B12 and RE B4 will be discussed with a few examples. The boron network provides a rich scenario for various lattice geometries that can lead to 1D, 2D and to 3D behaviour. This will be illustrated with a few examples: The frustrated fcc magnet HoB12 illustrates a new mechanism for lifting the frustration inherent to fcc - magnetism. TmB4 is a 2D Shastry Sutherland magnet where fractional magnetisation plateaus have been observed in magnetic field and we speculate this may be a magnetic analogue to fractional quantum Hall effect of a 2D electron gas. Finally, an example for a new type of 1D magnet will be presented.