High purity specimens of URu2Si2 produced by a molten metal flux technique

R.E Baumbach,Z Fisk,F Ronning,R Movshovich,J.D Thompson,E.D Bauer

doi:10.1080/14786435.2014.895876

Abstract

We report a molten metal flux technique to produce high purity specimens of URuSi. Magnetic susceptibility (), heat capacity () and electrical resistivity () measurements show that the bulk properties of these crystals are similar to those that are produced by the Czochralski technique followed by solid-state electro-transport. In particular, we find residual resistivity ratios RRR / as large as 220.

Highlights

For nearly three decades, URu2Si2 has been a central topic in the field of strongly correlated electrons, due to the fact that it exhibits two robust mean field second-order phase transitions: one at the “hidden order” temperature T0 ≈ 17.5 K and another at the superconducting phase transition Tc ≈ 0.8–1.4 K [1,2,3]
The hidden order transition is given its name because, roughly 0.2Rln2 of entropy is released at T0, intense experimental and theoretical efforts to uncover the order parameter have been unsuccessful: e.g. neutron scattering and μSR techniques yield ordered moments that are much too small to account for the entropy that is released at T0 [4,5]
Considerable interest has been paid to the superconducting state, which is clearly unconventional as evidenced by: (1) its occurrence deep inside the hidden order state [1,2,3], (2) the low carrier density from which it emerges [6,7], (3) the large upper critical field [8] and (4) measurements which suggest the presence of nodes in the superconducting energy gap [7,9,10,11]

Summary

Introduction

URu2Si2 has been a central topic in the field of strongly correlated electrons, due to the fact that it exhibits two robust mean field second-order phase transitions: one at the “hidden order” temperature T0 ≈ 17.5 K and another at the superconducting phase transition Tc ≈ 0.8–1.4 K [1,2,3]. High purity specimens of URu2Si2 produced by a molten metal flux technique

Results

Conclusion