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Effects of proximity to an electronic topological transition on normal state transport properties of the high-Tc superconductors

G. G. N. Angilella·R. Pucci·A. A. Varlamov·F. Onufrieva
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Abstract

Within the time dependent Ginzburg-Landau theory, the effects of the superconducting fluctuations on the transport properties above the critical temperature are characterized by a non-zero imaginary part of the relaxation rate gamma of the order parameter. Here, we evaluate Im gamma for an anisotropic dispersion relation typical of the high-Tc cuprate superconductors (HTS), characterized by a proximity to an electronic topological transition (ETT). We find that Im gamma abruptly changes sign at the ETT as a function of doping, in agreement with the universal behavior of the HTS. We also find that an increase of the in-plane anisotropy, as is given by a non-zero value of the next-nearest to nearest hopping ratio r=t'/t, increases the value of | Im gamma | close to the ETT, as well as its singular behavior at low temperature, therefore enhancing the effect of superconducting fluctuations. Such a result is in qualitative agreement with the available data for the excess Hall conductivity for several cuprates and cuprate superlattices.

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G. G. N. Angilella, R. Pucci, A. A. Varlamov, F. Onufrieva. 2003-03-13. Effects of proximity to an electronic topological transition on normal state transport properties of the high-Tc superconductors. https://doi.org/10.1103/physrevb.67.134525

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