Percolative nature of the dc paraconductivity in the cuprate superconductors

Petar Popčević; Damjan Pelc; Yang Tang; Kristijan Velebit; Zachary Anderson; Vikram Nagarajan; Guichuan Yu; Miroslav Požek; Neven Barišić; Martin Greven

doi:10.1038/s41535-018-0115-2

arXiv · 1710.10220

Percolative nature of the dc paraconductivity in the cuprate superconductors

Petar Popčević·Damjan Pelc·Yang Tang·Kristijan Velebit·Zachary Anderson·Vikram Nagarajan·Guichuan Yu·Miroslav Požek·Neven Barišić·Martin Greven

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Abstract

We present an investigation of the planar direct-current (dc) paraconductivity of the model cuprate material HgBa$_2$CuO$_{4+δ}$ in the underdoped part of the phase diagram. The simple quadratic temperature-dependence of the Fermi-liquid normal-state resistivity enables us to extract the paraconductivity above the macroscopic $T_c$ with great accuracy. The paraconductivity exhibits unusual exponential temperature dependence, with a characteristic temperature scale that is distinct from $T_c$. In the entire temperature range where it is discernable, the paraconductivity is quantitatively explained by a simple superconducting percolation model, which implies that underlying gap disorder dominates the emergence of superconductivity.

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Petar Popčević, Damjan Pelc, Yang Tang, Kristijan Velebit, Zachary Anderson, Vikram Nagarajan, Guichuan Yu, Miroslav Požek, Neven Barišić, Martin Greven. 2017-10-27. Percolative nature of the dc paraconductivity in the cuprate superconductors. https://doi.org/10.1038/s41535-018-0115-2

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