Locally critical quantum phase transitions in strongly correlated metals

Article

关键词: FERMI-LIQUID BEHAVIOR;    EXTENDED HUBBARD-MODEL;    MEAN-FIELD THEORY;    CRITICAL-POINT;    SPATIAL CORRELATIONS;    SPIN;    FLUCTUATIONS;    TEMPERATURE;    SYSTEMS;    ANTIFERROMAGNETISM;   

DOI  :  10.1038/35101507

来源: SCIE

【 摘 要 】

When a metal undergoes a continuous quantum phase transition, non-Fermi-liquid behaviour arises near the critical point. All the low-energy degrees of freedom induced by quantum criticality are usually assumed to be spatially extended, corresponding to long-wavelength fluctuations of the order parameter. But this picture has been contradicted by the results of recent experiments on a prototype system: heavy fermion metals at a zero-temperature magnetic transition. In particular, neutron scattering from CeCu6-xAux has revealed anomalous dynamics at atomic length scales, leading to much debate as to the fate of the local moments in the quantum-critical regime. Here we report our theoretical finding of a locally critical quantum phase transition in a model of heavy fermions. The dynamics at the critical point are in agreement with experiment. We propose local criticality to be a phenomenon of general relevance to strongly correlated metals.

【 授权许可】

Free