Density-matrix renormalisation group approach to quantum impurity problems
نویسندگان
چکیده
A dynamic density-matrix renormalisation group approach to the spectral properties of quantum impurity problems is presented. The method is demonstrated on the spectral density of the flat-band symmetric single-impurity Anderson model. We show that this approach provides the impurity spectral density for all frequencies and coupling strengths. In particular, Hubbard satellites at high energy can be obtained with a good resolution. The main difficulties are the necessary discretisation of the host band hybridised with the impurity and the resolution of sharp spectral features such as the Abrikosov-Suhl resonance. PACS numbers: 71.27.+a,71.55.Ak,72.15.Qm,78.67.Hc,05.10.Cc Submitted to: J. Phys.: Condens. Matter Density-matrix renormalisation group approach to quantum impurity problems 2
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