Universal low-temperature crossover in two-channel Kondo models

Article

关键词: CONFORMAL-FIELD-THEORY;    RENORMALIZATION-GROUP METHOD;    DILUTE MAGNETIC-ALLOYS;    FERMI-LIQUID BEHAVIOR;    LUTTINGER LIQUID;    ANDERSON MODEL;    FIXED-POINTS;    QUANTUM DOTS;    ISING-MODEL;    SELF-ENERGY;   

DOI  :  10.1103/PhysRevB.85.235127

来源: SCIE

【 摘 要 】

An exact expression is derived for the electron Green function in two-channel Kondo models with one and two impurities, describing the crossover from non-Fermi liquid (NFL) behavior at intermediate temperatures to standard Fermi liquid (FL) physics at low temperatures. Symmetry-breaking perturbations generically present in experiment ensure the standard low-energy FL description, but the full crossover is wholly characteristic of the unstable NFL state. Distinctive conductance lineshapes in quantum dot devices should result. We exploit a connection between this crossover and one occurring in a classical boundary Ising model to calculate real-space electron densities at finite temperature. The single universal finite-temperature Green function is then extracted by inverting the integral transformation relating these Friedel oscillations to the t matrix. Excellent agreement is demonstrated between exact results and full numerical renormalization group calculations.

【 授权许可】

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