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arXiv · 0906.1431

Fermi Surface Evolution in an Electron-Doped High-Tc Superconductor Revealed by Magnetic Quantum Oscillations

T. Helm·M. V. Kartsovnik·M. Bartkowiak·N. Bittner·M. Lambacher·A. Erb·J. Wosnitza·R. Gross
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Abstract

We report on the direct probing of the Fermi surface in the bulk of the electron-doped superconductor Nd$_{2-x}$Ce$_x$CuO$_4$ at different doping levels by means of magnetoresistance quantum oscillations. Our data reveal a sharp qualitative change in the Fermi surface topology, due to translational symmetry breaking in the electronic system which occurs at a critical doping level significantly exceeding the optimal doping. This result implies that the $(π/a,π/a)$ ordering, known to exist at low doping levels, survives up to the overdoped superconducting regime.

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T. Helm, M. V. Kartsovnik, M. Bartkowiak, N. Bittner, M. Lambacher, A. Erb, J. Wosnitza, R. Gross. 2009-08-14. Fermi Surface Evolution in an Electron-Doped High-Tc Superconductor Revealed by Magnetic Quantum Oscillations. https://doi.org/10.1103/physrevlett.103.157002

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