Showing papers by "Maheshwar Sharon published in 1994"

Silver doping and its influence on the oxygenation during in situ growth of YBa2Cu3O7−x thin films

Abstract: The influence of Ag doping on both oxygenation and deoxygenation during growth of YBa2Cu3O7−x films at 700 °C by pulsed laser deposition has been studied. Experiments show that undoped and Ag‐doped films grown at 200 mTorr oxygen pressure and quenched immediately after termination of growth have a superconducting transition temperature Tc of 61 and 86 K, respectively. The high Tc of 86 K obtained with quenched Ag‐doped films is thought to be due to both enhanced oxygen incorporation and reduced deoxygenation associated with Ag doping. These results show that Ag‐doped YBa2Cu3O7−x films could be crucial for realizing devices based on multilayer structures.

Aging effects and passivation studies on undoped and ag-doped yba2cu3o7-x laser-ablated thin-films

Abstract: The authors have examined the chemical stability of undoped and 5 weight percent Ag-doped YBa[sub 2]Cu[sub 3]O[sub 7[minus]x] thin films, both grown in situ by pulsed laser deposition technique. The studies indicate that Ag-doped films are more stable than undoped films. The improved chemical stability of Ag-doped films has been attributed to reduction in the effective area of intergranular regions and the presence of passivating silver clusters around grains. The study has also shown that coating the YBa[sub 2]Cu[sub 3]O[sub 7[minus]x] film surface with noble metals like Ag and Au results in passivation of YBa[sub 2]Cu[sub 3]O[sub 7[minus]x] films.