Quantum Critical Points in Quantum Impurity Systems

H. -J. Lee; R. Bulla

doi:10.1016/j.physb.2004.12.055

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Quantum Critical Points in Quantum Impurity Systems

H. -J. Lee·R. Bulla

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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.

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H. -J. Lee, R. Bulla. 2004-06-23. Quantum Critical Points in Quantum Impurity Systems. https://doi.org/10.1016/j.physb.2004.12.055

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