Epitaxial growth and properties of YBa2Cu3O7−δ/NdGaO3/YBa2Cu3O7−δ trilayer structures

We have used laser deposition to make YBa2Cu3O7−δ/NdGaO3/YBa2Cu3O7−δ trilayer structures. NdGaO3 films grow epitaxially on well lattice-matched substrates, like SrTiO3 (100), and on c-axis oriented YBa2Cu3O7−δ films. Epitaxial YBa2Cu3O7−δ films were grown on top of the NdGaO3 films, and there was no significant difference in critical temperature between top and bottom layers of the trilayer structures. The resistivity of a 300-nm-thick NdGaO3 interlayer was as high as 108 Ω cm at 300 K.