Quantum Critical Points in Quantum Impurity Systems
arXiv:cond-mat/0406557 · doi:10.1016/j.physb.2004.12.055
Abstract
The numerical renormalization group method is used to investigate zero temperature phase transitions in quantum impurity systems, in particular in the soft-gap Anderson model, where an impurity couples to a non-trivial fermionic bath. In this case, zero temperature phase transitions occur between two different phases whose fixed points can be built up of non-interacting single-particle states. However, the quantum critical point cannot be described by non-interacting fermionic or bosonic excitations.
2 pages, 3 figures, submitted to SCES'04