Rational material design of mixed-valent high-T-c superconductors

We design, from first-principles calculations, a novel family of thallium halide-based compounds as candidates for new high-temperature superconductors, whose superconductivity is mediated by the recently proposed mechanism of non-local correlation-enhanced strong electron-phonon coupling. Two prototype compounds namely CsTlF3 and CsTlCl3 are studied with various hole doping levels and volumes. The critical superconducting temperatures (T-c's) are predicted to be about 30K and 20K with similar to 0.35/f.u. hole doping and require only modest pressures (similar to 10 and similar to 2GPa), respectively. Our procedure of designing this class of superconductors is quite general and can be used to search for other other high-temperature superconductors. Copyright (C) EPLA, 2013