Lifshitz Transitions in the Ferromagnetic Superconductor UCoGe
  We present high field magnetoresistance, Hall effect and thermopower measurements in the Ising-type ferromagnetic superconductor UCoGe. Magnetic field is applied along the easy magnetization $c$ axis of the orthorhombic crystal. In the different experimental probes we observed five successive anomalies at $H \approx 4$, 9, 12, 16, and 21~T. Magnetic quantum oscillations were detected both in resistivity and thermoelectric power. At most of the anomalies, significant changes of the oscillation frequencies and the effective masses have been observed indicating successive Fermi surface instabilities induced by the strong magnetic polarization under magnetic field. 
Ga\"el Bastien, Adrien Gourgout, Dai Aoki, Alexandre Pourret, Ilya   Sheikin, Gabriel Seyfarth, Jacques Flouquet, Georg Knebel
cond-mat.str-el