Role Of Band Filling In Tuning The High-Field Phases Of Uru2si2

We present a detailed study of the low-temperature and high-magnetic-field phases in the chemical substitution series URu2Si2-P-x(x) using electrical transport and magnetization in pulsed magnetic fields up to 65 T. Within the hidden-order x regime (0 < x less than or similar to 0.035) the field-induced ordering that was earlier seen for x = 0 is robust, even as the hidden-order temperature is suppressed. Earlier work shows that for 0.035 less than or similar to x less than or similar to 0.26 there is a Kondo lattice with a no-ordered state that is replaced by antiferromagnetism for 0.26 less than or similar to x less than or similar to 0.5. We observe a simplified continuation of the field-induced order in the no-order x regime and an enhancement of the field-induced order upon the destruction of the antiferromagnetism with magnetic field. These results closely resemble what is seen for URu2-xRhxSi2,(1)from which we infer that charge tuning dominantly controls the ground state of URu2Si2, regardless of whether s/p or d electrons are replaced. Contraction of the unit-cell volume may also play a role at large x. This provides guidance for determining the specific factors that lead to hidden order versus magnetism in this family of materials and constrains possible models for hidden order.