Quantum oscillations in electron doped high temperature superconductors

Physical review. B, Condensed matter (Impact Factor: 3.66). 12/2009; 82(9). DOI: 10.1103/PhysRevB.82.094515
Source: arXiv


Quantum oscillations in hole doped high temperature superconductors are difficult to understand within the prevailing views. An emerging idea is that of a putative normal ground state, which appears to be a Fermi liquid with a reconstructed Fermi surface. The oscillations are due to formation of Landau levels. Recently the same oscillations were found in the electron doped cuprate, $\mathrm{Nd_{2-x}Ce_{x}CuO_{4}}$, in the optimal to overdoped regime. Although these electron doped non-stoichiometric materials are naturally more disordered, they strikingly complement the hole doped cuprates. Here we provide an explanation of these observations from the perspective of density waves using a powerful transfer matrix method to compute the conductance as a function of the magnetic field. Comment: An expanded version, accepted in Phys. Rev. B,

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    • "Assuming that the mean free paths for the hole and the electron pockets are more or less the same, the pockets with larger k F will be strongly suppressed because of the exponential sensitivity. This appears to be reasonable from whatever numerical calculations and approximate analytical calculations exist [65] [22]. Nonetheless, the definitive result in the resistive state of YBCO, including vortex fluctuations, is missing. "
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