Pressure-induced Fermi-liquid behavior in the Kondo insulator SmB6:: Possible transition through a quantum critical point -: art. no. 172406

We have investigated the electrical resistivity of the intermediate valence narrow-gap semiconductor SmB6 at temperatures below 80 K and under pressure in the range between 1 bar and 70 kbar. We report on a continuous suppression of the gap under pressure, and on the observation of a critical point at p(cr)approximate to40 kbar, characterizing the pressure induced transition from a Kondo insulator below p(cr) to a metallic heavy fermion liquid well above p(cr). In the metallic phase close to p(cr) strong indications for a non-Fermi-liquid region, in which the electrical resistivity can be described by a power law rho(T)=rho(0)+AT(n) with 1less than or equal tonless than or equal to2, were observed.