Anomalous scaling behavior of the dynamical spin susceptibility of Ce0.925La0.075Ru2Si2

Article

关键词: QUANTUM-CRITICAL-POINT;    INELASTIC NEUTRON-SCATTERING;    FERMION COMPOUND CERU2SI2;    MAGNETIC INSTABILITY;    TRANSPORT-PROPERTIES;    LIQUID BEHAVIOR;    HEAVY-ELECTRON;    FLUCTUATIONS;    DEPENDENCE;    PRESSURE;   

DOI  :  10.1103/PhysRevB.70.174401

来源: SCIE

【 摘 要 】

Inelastic neutron scattering measurements have been performed on single crystals of the heavy-fermion compound Ce0.925La0.075Ru2Si2 in broad energy [0.1,9.5 meV] and temperature [40 mK,294 K] ranges in order to address the question of scaling behavior of the dynamical spin susceptibility at the quantum critical point of an itinerant magnetic system. For two wave vectors Q corresponding to uncorrelated and antiferromagnetically correlated spin fluctuations, it is found that the dynamical spin susceptibility chi(')(Q,E,T) is independent of temperature below a cutoff temperature T-Q: the spin fluctuation amplitude saturates at low temperatures contrarily to its expected divergence at a quantum critical point. Above T-Q, a Q-dependent scaling behavior of the form Tchi(')(Q,E,T)=C(Q)f[E/(a(Q)T(Q)(beta))] with beta(Q)<1 is obtained. This scaling does not enter the general framework of quantum phase transition theories, since it is obtained in a high-temperature range, where Kondo spin fluctuations depend strongly on temperature.

【 授权许可】

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