Single-Crystal like MgB2thin films grown on c-cut sapphire substrates

Abstract

Abstract Single-crystal like MgB 2 thin film was grown on (000) Al 2 O l3 substrate by using hybrid physical-chemical vapor deposition (HPCVD) system. Single crystal were properties studied by X-ray diffraction (XRD)and the full width half maximum at (FWHM) of the (0001) MgB 2 peak is 0.15°, which is very close to that has been reported for MgB 2 single-crystal. It indicates that the crystalline quality of thin film is good. Temperature dependence on resistivity was investigated by physical property measurement system (PPMS) in various applied fields from 0 to 9 T. The upper critical field ( H c2 ) and irreversibility field ( H irr ) were determined from PPMS data, the estimated values arand e comparable with that of MgB 2 single-crystals. The thin film shows a high critical temperature ( T c ) of 40.4 K with a sharp superconducting transition width of 0.2 K, and a high residual resistivity ratio (RRR=21), it reflects that MgB 2 thin film has a pure phase structure. Keywords