2000/11/01 by Sebastian Eggert, David Gustafsson, David P. Gustafsson +1 · 1 citation
Mathematics · Physics and Astronomy · #Antiferromagnetism #Condensed matter physics #Coupling (piping) #Fixed point #Impurity #Kondo effect #Kondo model #Materials science #Mathematical analysis #Mathematics #Phase (matter) #Phase diagram #Physics #Physics of Superconductivity and Magnetism #Quantum and electron transport phenomena #Quantum many-body systems #Quantum mechanics #Spin (aerodynamics) #Thermodynamics #cond-mat.mes-hall #cond-mat.str-el
paper · pdf · doi:10.1103/physrevlett.86.516
published as Phys. Rev. Lett. 86, p. 516 (2001). · 5 pages in revtex format including 4 embedded figures (using epsf). The latest version in PDF format is available from http://fy.chalmers.se/~eggert/papers/phase-diagram.pdf
arxiv created 2000/11/01 · openalex publication_date 2001/01/15 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We consider a magnetic S = 1/2 impurity in the antiferromagnetic spin chain as a function of two coupling parameters: the symmetric coupling of the impurity to two sites in the chain J1 and the coupling between the two sites J2. By using field theory arguments and numerical calculations we can identify all possible fixed points and classify the renormalization flow between them, which leads to a nontrivial phase diagram. Depending on the detailed choice of the two (frustrating) coupling strengths, the stable phases correspond either to a decoupled spin with Curie law behavior or to a non-Fermi-liquid fixed point with a logarithmically diverging impurity susceptibility as in the two-channel Kondo effect. Our results resolve a controversy about the renormalization flow.