Non-Fermi liquid transport and "universal" ratios in quantum Griffiths phases

Abstract

We use the semi-classical Boltzmann equation to investigate transport properties such as electrical resistivity, thermal resistivity, thermopower, and the Peltier coefficient of disordered metals close to an antiferromagnetic quantum phase transition. In the quantum Griffiths phase, the electrons are scattered by spin-fluctuations in the rare regions. This leads to singular temperature dependencies not just at the quantum critical point, but in the entire Griffiths phase. We show that the resulting non-universal power-laws in transport properties are controlled by the same Griffiths exponent $\lambda$ which governs the thermodynamics. $\lambda$ takes the value zero at the quantum critical point and increases throughout the Griffiths phase. We also study some of the "universal" ratios commonly used to characterize Fermi-liquid behavior.

6 pages, submitted to the Proceedings of SCES 2011, Cambridge, UK

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Cited by in corpus (2)

• Non-Fermi liquid behaviour from dynamical effects of impurity scattering in correlated Fermi liquids
• Strong-disorder magnetic quantum phase transitions: Status and new developments