School of Physics & Astronomy

# Publications

### Martin Greven

Universal sheet resistance and revised phase diagram of the cuprate high-temperature superconductors
N. Barišić, Y. Li, G. Yu, X. Zhao, M. Dressel, A. Smontara and M. Greven, Proc. Nat. Acad. Sci. 110.12235 (2013)

In the enigmatic lamellar cuprates, strong electronic correlations give rise to an insulating parent state from which superconductivity and eventually a Fermi-liquid-like metal emerge upon doping. At intermediate hole concentrations (p), the deviation from a linear-in-temperature planar resistivity (\rho $\propto$ T) upon cooling toward the superconducting state is associated with the opening of a 'pseudogap' in the antinodal regions of the Fermi surface. Contrary to common belief, we find in the pseudogap phase of structurally simple HgBa$_2$CuO$_{4+\delta}$ that \rho $\propto$ T$^2$, as in the putative Fermi-liquid state at high doping. By combining these results with prior work for other cuprates, we are able to obtain the fundamental resistance per copper-oxygen plaquette in both the linear (\rho_S = A_{1S} T) and quadratic (\rho_S = A_{2S} T$^2$) regimes, with A_{1S} $\propto$ A_{2S} $\propto$ 1/p. Any theory for the cuprates can now be benchmarked against this simple universal behavior of the planar resistivity.