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Interplay between Fermi surface topology and ordering in URu$_{2}$Si$_2$ revealed through abrupt Hall coefficient changes in strong magnetic fields

Y. S. Oh·Kee Hoon Kim·P. A. Sharma·N. Harrison·H. Amitsuka·J. A. Mydosh
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Abstract

Temperature- and field-dependent measurements of the Hall effect of pure and 4 % Rh-doped URu$_{2}$Si$_{2}$ reveal low density (0.03 hole/U) high mobility carriers to be unique to the `hidden order' phase and consistent with an itinerant density-wave order parameter. The Fermi surface undergoes a series of abrupt changes as the magnetic field is increased. When combined with existing de Haas-van Alphen data, the Hall data expose a strong interplay between the stability of the `hidden order,' the degree of polarization of the Fermi liquid and the Fermi surface topology.

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Y. S. Oh, Kee Hoon Kim, P. A. Sharma, N. Harrison, H. Amitsuka, J. A. Mydosh. 2006-11-30. Interplay between Fermi surface topology and ordering in URu$_{2}$Si$_2$ revealed through abrupt Hall coefficient changes in strong magnetic fields. https://doi.org/10.1103/physrevlett.98.016401

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