Evolution toward Quantum Critical End Point in UGe_2
  We report on Hall resistivity and electrical resistivity measurements under pressure and magnetic field in UGe_2 with ferromagnetic (FM) tricriticality. The Hall resistivity sensitively detects the first order metamagnetic transition from a paramagnetic (PM) phase to a FM phase in a large pressure range almost up to the quantum critical end point (QCEP). The drastic change in the Fermi surface at the PM-FM transition is detected up to the vicinity of the QCEP, while a strong modification in the field variation of the inelastic scattering between electrons is observed toward the QCEP. The comparison with the theoretical predictions is made. 
Hisashi Kotegawa, Valentin Taufour, Dai Aoki, Georg Knebel, Jacques   Flouquet
cond-mat.str-el