RESUMO
The fundamental parameters of the superconducting state such as coherence length and pairing strength are essential for understanding the nature of superconductivity. These parameters can be estimated by measuring critical parameters such as upper critical field, Hc2. In this work, Hc2 of a superconducting (110) LaAlO3/SrTiO3 interface is determined through magnetoresistive measurements as a function of the gate voltage, VG. When VG increases, the critical temperature has a dome-like shape, while Hc2 monotonically decreases. This relationship of independence between the variation of Tc and of Hc2 suggests that the Cooper pairing potential is stronger in the underdoped region and the coherence length increases with the increase of VG. The result is as for high temperature superconducting cuprates and it is different than for conventional low temperature superconductors.
RESUMO
We report a generally applicable method to pattern organic molecules on mesoscopic scales. In our method, organic molecular beam deposition was conducted on substrate surfaces prepatterned with materials to which the organic molecules have larger binding energies in comparison to the substrate. Fully uniform nucleation control at these predefined locations can be achieved by an appropriate selection of the growth parameters including temperature and deposition rate. The physical mechanisms involved are studied by Monte Carlo simulations and stand in good agreement with the experimental findings.
