Non-Fermi-liquid fixed point | |
Article | |
关键词: NUMERICAL RENORMALIZATION-GROUP; 2-LEVEL TUNNELING SYSTEMS; LOW-TEMPERATURE PROPERTIES; DILUTE MAGNETIC-ALLOYS; CONFORMAL FIELD-THEORY; ANDERSON MODEL; KONDO PROBLEM; ELECTRON MATERIALS; STATIC PROPERTIES; IMPURITIES; | |
DOI : 10.1103/PhysRevB.55.12460 | |
来源: SCIE |
【 摘 要 】
We study an exchange interaction in which conduction electrons with pseudospin S-c=3/2 interact with the impurity spin S-l=1/2. Due to the overscreening of the impurity spin by higher conduction electron spin, a nontrivial intermediate-coupling-strength fixed point is realized. Using the numerical renormalization group (NRG), we show that the low-energy spectra are described by a non-Fermi-liquid excitation spectrum. A conformal field theory analysis is compared with NRG results and excellent agreement is obtained. Using the double-fusion rule to generate the operator spectrum with the conformal theory, we find that the specific heat coefficient and magnetic susceptibility will diverge as T-2/3, that the scaling dimension of an applied magnetic field is 5/6, and that exchange anisotropy is always relevant. We discuss the possible relevance of our work to two-level-system Kondo materials and dilute cerium alloys, and we point out a paradox in understanding the Bethe-ansatz solutions to the multichannel Kondo model.
【 授权许可】
Free