61 citations · 98 across the 2 of their papers we have counts for
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Berry Phase and the Breakdown of the Quantum to Classical Mapping for the Quantum Critical Point of the Bose-Fermi Kondo model
Stefan Kirchner, Qimiao Si
The phase diagram of the Bose-Fermi Kondo model contains an SU(2)-invariant Kondo-screened phase separated by a continuous quantum phase transition from a Kondo-destroyed local mom…
Quantum Criticality in Ferromagnetic Single-Electron Transistors
Stefan Kirchner, Lijun Zhu, Qimiao Si +1
Considerable evidence exists for the failure of the traditional theory of quantum critical points (QCPs), pointing to the need to incorporate novel excitations. The destruction of…
Quantum critical properties of the Bose-Fermi Kondo Model in a large-N limit
Lijun Zhu, Stefan Kirchner, Qimiao Si +1
Studies of non-Fermi liquid properties in heavy fermions have led to the current interest in the Bose-Fermi Kondo model. Here we use a dynamical large-N approach to analyze an SU(N…
Self-consistent Conserving Theory for Quantum Impurity Systems: Renormalization Group Analysis
Stefan Kirchner, Johann Kroha
We review the diagrammatic, conserving theory for quantum impurities with strong on-site repulsion. The method is based on auxiliary particle technique, where Wick's theorem is val…
Transport Properties of One-Dimensional Hubbard Models
S. Kirchner, H. G. Evertz, W. Hanke
We present results for the zero and finite temperature Drude weight D(T) and for the Meissner fraction of the attractive and the repulsive Hubbard model, as well as for the model w…