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arXiv · 1107.0258

Colloquium: Hidden Order, Superconductivity, and Magnetism -- The Unsolved Case of URu2Si2

J. A. Mydosh·P. M. Oppeneer
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Abstract

This Colloquium reviews the 25 year quest for understanding the continuous (second-order) mean-field-like phase transition occurring at 17.5 K in URu2Si2. About ten years ago, the term hidden order (HO) was coined and has since been utilized to describe the unknown ordered state, whose origin cannot be disclosed by conventional solid-state probes, such as x rays, neutrons, or muons. HO is able to support superconductivity at lower temperatures (Tc ~ 1.5 K), and when magnetism is developed with increasing pressure both the HO and the superconductivity are destroyed. Other ways of probing the HO are via Rh-doping and very large magnetic fields. During the last few years a variety of advanced techniques have been tested to probe the HO state and their attempts will be summarized. A digest of recent theoretical developments is also included. It is the objective of this Colloquium to shed additional light on the HO state and its associated phases in other materials.

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J. A. Mydosh, P. M. Oppeneer. 2011-07-01. Colloquium: Hidden Order, Superconductivity, and Magnetism -- The Unsolved Case of URu2Si2. https://doi.org/10.1103/revmodphys.83.1301

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