TRANSPORT PROPERTIES OF La2-x1Srx1CuO4+delta/La2-x2Srx2CuO4+delta MULTILAYERS GROWN BY LASER ABLATION

A series of La2-x1Srx1CuO4+delta/La(2-x2)Srx(2)CuO(4+delta) multilayers were epitaxially grown on (001) LaSrAlO4 and (001) SrTiO3 substrates by laser ablation, where x1 = 0.0, 0.08 (underdoped) and x2 = 0.24, 0.32, 0.45 (over-doped). Before the depositions of each multilayer, all of the single layers were deposited and characterized, and then the multilayers were deposited by using the same deposition condition except shifting targets for laser ablation. These multilayers are highly c-axis oriented. Several modulation wavelengths of the sublayers were selected for preparing the multilayers. The resistance measurements of these single layered films of La2-x1Srx1CuO4+delta, La2-x2Srx2CuO4+delta, and multilayers of La2-x1Srx1CuO4+delta/La2-x2Srx2CuO4+delta were performed and compared. The transport measurements suggest that the charge redistribution may be a dominant factor for the superconducting transition temperature in low temperatures.