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Shubnikov de Haas effect in the metallic state of Na$_{0.3}$CoO$_2$

L. Balicas·J. G. Analytis·Y. J. Jo·K. Storr·H. Zandbergen·Y. Xin·N. E. Hussey·F. C. Chou·P. A. Lee
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Abstract

Shubnikov de Haas oscillations for two well defined frequencies, corresponding respectively to areas of 0.8 and 1.36% of the first Brillouin zone (FBZ), were observed in single crystals of Na$_{0.3}$CoO$_2$. The existence of Na superstructures in Na$_{0.3}$CoO$_2$, coupled with this observation, suggests the possibility that the periods are due to the reconstruction of the large Fermi surface around the $Γ$ point. An alternative interpretation in terms of the long sought-after $ε_g^\prime$ pockets is also considered but found to be incompatible with existing specific heat data.

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L. Balicas, J. G. Analytis, Y. J. Jo, K. Storr, H. Zandbergen, Y. Xin, N. E. Hussey, F. C. Chou, P. A. Lee. 2006-05-18. Shubnikov de Haas effect in the metallic state of Na$_{0.3}$CoO$_2$. https://doi.org/10.1103/physrevlett.97.126401

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