Resistivity in Cuprates and the Pseudogap

Artikel i vetenskaplig tidskrift, 2017

The temperature dependence of resistivity (rho) in the normal state of La2-x Sr (x) CuO4 is calculated from electron transfer (ET) rates. The minimum at about 100 K for doping levels less than 6 % is characteristic for all cuprates. The resistivity depends on ET between Cu(III) and Cu(II) sites. For T < 300 K, the resistivity is proportional to T (3/2). The more than linear increase of rho for T > 100 K depends on increased kinetic energy in a Landau avoided crossing. The agreement with experimental data is convincing. The behaviour for T -> 0 can be explained as nuclear tunnelling. For T > 400 K, rho bends down, presumably because the pseudogap is overcome at a higher kinetic energy.