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A series of c-axis oriented electron-doped high-Tc superconducting La(2-x)CexCuO4 thin films, from heavily underdoped x=0.06 to heavily overdoped x=0.19, have been synthesized by dc magnetron sputtering technique on (100) SrTiO3 substrates. The influence of various fabrication conditions, such as the deposition temperature and the deposition rate, etc., on the quality of the thin films has been scrutinized. We find that the quality of the films is less sensitive to the deposition temperature in the overdoped region than that in the underdoped region. In the phase diagram of Tc(x), the superconducting dome indicates that the optimally doping level is at the point x=0.105 with the transition temperature Tc0 = 26.5 K. Further more, both the disappearance of the upturn in the $rho_{xx}$(T) curve at low temperature under H=10 T and the positive differential Hall coefficient, $R_H=d rho_{xy}/dH$, are observed around x = 0.15, implying a possible rearrangement of Fermi surface at this doping level.
A series of electron-doped cuprate La(2-x)CexCuO4 thin films with different thicknesses have been fabricated and their annealing time are adjusted carefully to ensure the highest superconducting transition temperature. The transport measurements indi
We have used the electric--field effect to modulate the resistivity of the surface of underdoped Sr$_{0.88}$La$_{0.12}$CuO$_{2+x}$ thin films, allowing opposite modifications of the electron and hole density in the CuO$_2$ planes, an original situati
We performed systematic angle-resolved photoemission spectroscopy measurements $in$-$situ$ on $T$-${rm La}_{2-x}{rm Ce}_xrm {CuO}_{4pmdelta}$ (LCCO) thin films over the extended doping range prepared by the refined ozone/vacuum annealing method. Elec
Electron correlations play a dominant role in the charge dynamics of the cuprates. We use resonant inelastic x-ray scattering (RIXS) to track the doping dependence of the collective charge excitations in electron doped La$_{2-x}$Ce$_{x}$CuO$_{4}$(LCC
We fabricated superconducting MgB2 thin films on (001) MgO substrates. The samples were prepared by magnetron rf and dc co-sputtering on heated substrates. They were annealed ex-situ for one hour at temperatures between 450{deg}C and 750{deg}C. We wi