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arXiv · 0707.4461

Shubnikov-de Haas oscillations in YBa_2Cu_4O_8

A. F. Bangura·J. D. Fletcher·A. Carrington·J. Levallois·M. Nardone·B. Vignolle·P. J. Heard·N. Doiron-Leyraud·D. LeBoeuf·L. Taillefer·S. Adachi·C. Proust·N. E. Hussey
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Abstract

We report the observation of Shubnikov-de Haas oscillations in the underdoped cuprate superconductor YBa$_2$Cu$_4$O$_8$ (Y124). For field aligned along the c-axis, the frequency of the oscillations is $660\pm 30$ T, which corresponds to $\sim 2.4$ % of the total area of the first Brillouin zone. The effective mass of the quasiparticles on this orbit is measured to be $2.7\pm0.3$ times the free electron mass. Both the frequency and mass are comparable to those recently observed for ortho-II YBa$_2$Cu$_3$O$_{6.5}$ (Y123-II). We show that although small Fermi surface pockets may be expected from band structure calculations in Y123-II, no such pockets are predicted for Y124. Our results therefore imply that these small pockets are a generic feature of the copper oxide plane in underdoped cuprates.

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A. F. Bangura, J. D. Fletcher, A. Carrington, J. Levallois, M. Nardone, B. Vignolle, P. J. Heard, N. Doiron-Leyraud, D. LeBoeuf, L. Taillefer, S. Adachi, C. Proust, N. E. Hussey. 2007-12-17. Shubnikov-de Haas oscillations in YBa_2Cu_4O_8. https://doi.org/10.1103/physrevlett.100.047004

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