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arXiv · 1504.08104

Quantum Oscillations and Magnetic Reconstruction in the Delafossite PdCrO$_2$

Clifford W. Hicks·Alexandra S. Gibbs·Lishan Zhao·Pallavi Kushwaha·Horst Borrmann·Andrew P. Mackenzie·Hiroshi Takatsu·Shingo Yonezawa·Yoshiteru Maeno·Edward A. Yelland
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Abstract

We report quantum oscillation data on the metallic triangular antiferromagnet PdCrO$_2$. We find that, to very high accuracy, the observed frequencies of PdCrO$_2$ can be reproduced by reconstruction of the (nonmagnetic) PdCoO$_2$ Fermi surface into a reduced zone. The reduced zone corresponds to a magnetic cell containing six chromium sites, giving a $\sqrt{3} \times \sqrt{3}$ in-plane reconstruction, and $\times 2$ interplane reconstruction. The interplane ordering represents a reduction in lattice symmetry, possibly to monoclinic, and an associated lattice distortion is expected. In addition, we report a magnetic transition under an applied in-plane field that is probably equivalent to the spin-flop transition reported for CuCrO$_2$, and present data on its field-angle dependence. We also report measurements of the resistivity of PdCrO$_2$ up to 500 K.

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Clifford W. Hicks, Alexandra S. Gibbs, Lishan Zhao, Pallavi Kushwaha, Horst Borrmann, Andrew P. Mackenzie, Hiroshi Takatsu, Shingo Yonezawa, Yoshiteru Maeno, Edward A. Yelland. 2015-04-30. Quantum Oscillations and Magnetic Reconstruction in the Delafossite PdCrO$_2$. https://arxiv.org/abs/1504.08104

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