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Fractionalization and Fermi surface volume in heavy fermion compounds: the case of YbRh$_2$ Si$_2$

Catherine Pepin
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Abstract

We establish an effective theory for heavy fermion compounds close to a zero temperature Anti-Ferromagnetic (AF) transition. Coming from the heavy Fermi liquid phase across to the AF phase, the heavy electron fractionalizes into a light electron, a bosonic spinon and a {\it new} excitation: a spinless fermionic field. Assuming this field acquires dynamics and dispersion when one integrates out the high energy degrees of freedom, we give a scenario for the volume of its Fermi surface through the phase diagram. We apply our theory to the special case of YbRh$_2$(Si$_{1-x}$ Ge$_x$)$_2$ where we recover, within experimental resolution, several low temperature exponents for transport and thermodynamics.

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Catherine Pepin. 2004-07-07. Fractionalization and Fermi surface volume in heavy fermion compounds: the case of YbRh$_2$ Si$_2$. https://doi.org/10.1103/physrevlett.94.066402

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