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arXiv · 1010.1288

Similarity of Fermi Surface in the Hidden Order State and in the Antiferromagnetic State of URu2Si2

E. Hassinger·G. Knebel·T. M. Matsuda·D. Aoki·V. Taufour·J. Flouquet
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Abstract

Shubnikov-de Haas measurements of high quality URu2Si2 single crystals reveal two previously unobserved Fermi surface branches in the so-called hidden order phase. Therefore about 55% of the enhanced mass is now detected. Under pressure in the antiferromagnetic state, the Shubnikov-de Haas frequencies for magnetic fields applied along the crystalline c axis show little change compared with the zero pressure data. This implies a similar Fermi surface in both the hidden order and antiferromagnetic states, which strongly suggests that the lattice doubling in the antiferromagnetic phase due to the ordering vector QAF = (0 0 1) already occurs in the hidden order. These measurements provide a good test for existing or future theories of the hidden order parameter.

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E. Hassinger, G. Knebel, T. M. Matsuda, D. Aoki, V. Taufour, J. Flouquet. 2010-10-06. Similarity of Fermi Surface in the Hidden Order State and in the Antiferromagnetic State of URu2Si2. https://doi.org/10.1103/physrevlett.105.216409

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