Search for a quantum critical end-point in CeRu2(Si1-xGex)2

We use high-resolution dilatometry and electrical resistivity down to 20 mK and millitesla magnetic field steps to search for a possible quantum critical (end-) point (QC(E)P) in CeRu2(Si1-xGex)(2) with x = 0.00 and 0.02 at the metamagnetic transition (MMT), B-m = 7.8 and 6.8 T, respectively. We do not find any evidence for QCEP since (i) the peak height and FWHM of the magnetostrictive anomaly saturate below 0.2 K and (ii) the thermal expansion and the electrical resistivity indicate the formation of a Landau-Fermi liquid (LFL) state below 0.3 K even at B = B-m. We speculate that the metamagnetic crossover represents a Fermi surface reconstruction that is fully completed below 0.2 K. (c) 2005 Elsevier B.V. All rights reserved.