arXiv subjects

J. Fompeyrine

Publications and source records attributed to J. Fompeyrine.

2 recordsLinked to original sources

arXiv2006

Electrostatic Modulation of the Superfluid Density in a Ultrathin La2-xSrxCuO4 Film

By capacitively charging an underdoped ultrathin La2-xSrxCuO4 film with an electric field applied across a gate insulator with a high dielectric constant, relative changes of the areal superfluid density n_{s\Box}$ of unprecedented strength were observed in measurements of the film kinetic inductance. Although $n_{s\Box}$ appears to be substantially reduced by disorder, the data provide, for the first time on the same sample, direct compelling evidence for the Uemura relation $T_{c} \propto n_{s\Box}(T=0)$ in the underdoped regime of copper-oxide superconductors.

cond-mat.supr-con↗

arXiv2003

Growth of Single Unit-Cell Superconducting La$_{2-x}$Sr$_x$CuO$_{4}$ Films

We have developed an approach to grow high quality ultrathin films of La$_{2-x}$Sr$_x$CuO$_{4}$ with molecular beam epitaxy, by adding a homoepitaxial buffer layer in order to minimize the degradation of the film structure at the interface. The advantage of this method is to enable a further reduction of the minimal thickness of a superconducting La$_{1.9}$Sr$_{0.1}$CuO$_{4}$ film. The main result of our work is that a single unit cell (only two copper oxide planes) grown on a SrLaAlO$_4$ substrate exhibits a superconducting transition at 12.5 K (zero resistance) and an in-plane magnetic penetration depth $λ_{ab}(0)$ = 535 nm.

cond-mat.supr-con↗