Quantum oscillations in underdoped YBa_2Cu_3O_6.5

Cyril Jaudet; Julien Levallois; Alain Audouard; David Vignolles; Baptiste Vignolle; Ruixing Liang; D. A. Bonn; W. N. Hardy; N. E. Hussey; Louis Taillefer; Cyril Proust

doi:10.1016/j.physb.2008.11.029

arXiv · 1001.1508

Quantum oscillations in underdoped YBa_2Cu_3O_6.5

Cyril Jaudet·Julien Levallois·Alain Audouard·David Vignolles·Baptiste Vignolle·Ruixing Liang·D. A. Bonn·W. N. Hardy·N. E. Hussey·Louis Taillefer·Cyril Proust

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Abstract

Shubnikov-de Haas and de Haas-van Alphen effects have been measured in the underdoped high temperature superconductor YBa$_2$Cu$_3$O$_{6.51}$. Data are in agreement with the standard Lifshitz-Kosevitch theory, which confirms the presence of a coherent Fermi surface in the ground state of underdoped cuprates. A low frequency $F = 530 \pm 10$ T is reported in both measurements, pointing to small Fermi pocket, which corresponds to 2% of the first Brillouin zone area only. This low value is in sharp contrast with that of overdoped Tl$_2$Ba$_2$CuO$_{6+δ}$, where a high frequency $F = 18$ kT has been recently reported and corresponds to a large hole cylinder in agreement with band structure calculations. These results point to a radical change in the topology of the Fermi surface on opposing sides of the cuprate phase diagram.

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Cyril Jaudet, Julien Levallois, Alain Audouard, David Vignolles, Baptiste Vignolle, Ruixing Liang, D. A. Bonn, W. N. Hardy, N. E. Hussey, Louis Taillefer, Cyril Proust. 2010-01-10. Quantum oscillations in underdoped YBa_2Cu_3O_6.5. https://doi.org/10.1016/j.physb.2008.11.029

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