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arXiv · 0912.4521

Critical Kondo destruction in a pseudogap Anderson model: scaling and relaxational dynamics

Matthew T. Glossop·Stefan Kirchner·J. H. Pixley·Qimiao Si
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Abstract

We study the pseudogap Anderson model as a prototype system for critical Kondo destruction. We obtain finite-temperature (T) scaling functions near its quantum critical point, using a continuous-time quantum Monte Carlo method and also considering a dynamical large-N limit. We are able to determine the behavior of the scaling functions in the typically-difficult-to-access quantum-relaxational regime (hbar w < k_B T), and conclude that the relaxation rates for both the spin and single-particle excitations are linear in temperature. We discuss the implications of these results for the quantum critical phenomena in heavy fermion metals.

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Matthew T. Glossop, Stefan Kirchner, J. H. Pixley, Qimiao Si. 2011-10-12. Critical Kondo destruction in a pseudogap Anderson model: scaling and relaxational dynamics. https://doi.org/10.1103/physrevlett.107.076404

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