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Field-Dependent Hall Effect in Single Crystal Heavy Fermion YbAgGe below 1K

S. L. Bud'ko·V. Zapf·E. Morosan·P. C. Canfield
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Abstract

We report the results of a low temperature (T >= 50 mK) and high field (H <= 180 kOe) study of the Hall resistivity in single crystals of YbAgGe, a heavy fermion compound that demonstrates field-induced non-Fermi-liquid behavior near its field-induced quantum critical point. Distinct features in the anisotropic, field-dependent Hall resistivity sharpen on cooling down and at the base temperature are close to the respective critical fields for the field-induced quantum critical point. The field range of the non-Fermi-liquid region decreases on cooling but remains finite at the base temperature with no indication of its conversion to a point for T -> 0. At the base temperature, the functional form of the field-dependent Hall coefficient is field direction dependent and complex beyond existing simple models thus reflecting the multi-component Fermi surface of the material and its non-trivial modification at the quantum critical point.

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S. L. Bud'ko, V. Zapf, E. Morosan, P. C. Canfield. 2005-07-14. Field-Dependent Hall Effect in Single Crystal Heavy Fermion YbAgGe below 1K. https://doi.org/10.1103/physrevb.72.172413

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