Scopul nostru este sprijinirea şi promovarea cercetării ştiinţifice şi facilitarea comunicării între cercetătorii români din întreaga lume.
Autori: B Andraka, C R Rotundu, P Kumar, and H Tsujii
Editorial: IOP, Journal of Physics: Condensed Matter, 22, p.345701, 2010.
Measurements of the upper critical field Hc2 near Tc of Pr1-xLaxOs4Sb12 were performed by specific heat. The results support the hypothesis of a non-single-ion origin of m* enhancement in PrOs4Sb12, derived from the analysis of the C/T discontinuity at Tc. Both sets of measurements indicate the existence of a crossover concentration, xcr~0.2–0.3, separating heavy fermion-like alloys (x < xcr) from normal metals (x > xcr). Heavy fermion-like alloys exhibit field-induced long-range antiferro-quadrupolar (AFQ) anomalies in the specific heat, while those with x > xcr do not. The curvature in Hc2 versus T near Tc, observed in different measurements on pure PrOs4Sb12, is sample- and method-dependent.
Cuvinte cheie: heavy fermion superconductor PrOs4Sb12