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

TL;DR

This study investigates how the Fermi surface topology and electronic order in URu$_{2}$Si$_{2}$ change under magnetic fields, revealing abrupt Fermi surface modifications linked to the hidden order phase through Hall effect measurements.

Contribution

It provides new insights into the relationship between Fermi surface topology and hidden order in URu$_{2}$Si$_{2}$ using Hall effect and de Haas-van Alphen data.

Findings

Low density, high mobility carriers are unique to the hidden order phase.

The Fermi surface undergoes abrupt changes with increasing magnetic field.

The data show a strong interplay between hidden order stability and Fermi surface topology.

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.