Studies on La0.7Ca0.3MnO3-YBa2Cu3O7-delta heterostructures grown by pulsed laser deposition technique

Pulsed laser deposition (PLD) is a unique method for growing highly stoichiometric, materials in the form of epitaxial thin films. Here we discuss the optimization of deposition parameters for laser ablation of multi-component La0.7Ca0.3MnO3-YBa2Cu3O7-delta (LCMO-YBCO) heterostructures grown in situ by sequential deposition of LCMO and YBCO on (100) LaAlO3 (LAO) substrates using a PLD system. We discuss the growth of these multi-layers, from the device applications point of view

YBa

$\rm Ba_2\!\!LaMb\!\!O_6$, a new perovskite substrate material for $\rm Y\!\!ptBa_2\!\!Cu_3\!\!O_{7\hbox{-}\delta}$, has been grown epitaxially on (100) MgO by pulsed-laser ablation method. A superconducting $\rm Y Ba_2Cu_3O_{7\hbox{-}\delta}$ film in situ grown on an epitaxial $\rm Ba_2LaNbO_6$ film gave a $T_{\rm C}(0)=90\;{\rm K}$ with a transition width $\Delta T=0.5\;{\rm K}$. The $\rm YBa_2Cu_3O_{7\hbox{-}\delta}$ films exhibited $(00\ell)$ orientation of an orthorhombic $\rm YBa_2Cu_3O_{7\hbox{-}\delta}$ phase and showed almost perfect metallic behaviour in the normal state with resistance ratio $(R_{\rm 300K}/R_{\rm 100K})=2.98$. Critical current density of $5\times 10^6\;{\rm A/cm^2}$ at 77 K was obtained consistently for the $\rm YBa_2Cu_3O_{7\hbox{-}\delta}$ films in situ grown on epitaxial $\rm Ba_2LaNbO_6$ films