Structural and physical properties of ultra thin films of Bi2Sr2CuO6 and Bi2(Sr,Ca)3Cu2O8 formed by a low temperature (<673 K) molecular beam epitaxy (MBE) method using 10-5Pa of NO2 as an oxidant are presented. On the substrates with less than 3% lattice mismatch, epitaxial growth from the substrate surface is realized, resulting in the formation of strained lattices. For the substrate with a big lattice mismatch of 10% (MgO), the observed lattice constants were similar to that for the bulk material. A superconducting transition with the onset Tc of 90K and the zero-resistance of 40K was obtained for the Bi2(Sr,Ca)3Cu2Ox/MgO(100) by post annealing at 1093K with O2. The optical absorption of the film indicate that annealing with O2 gives rise to an increase in the carrier concentration.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Energy Engineering and Power Technology
- Electrical and Electronic Engineering