Oxygen was systematically incorporated in MgB2 films using in situ postgrowth anneals in an oxygen environment. Connectivity analysis in combination with measurements of the critical temperature (Tc) and resistivity (ρ) indicate that oxygen is distributed both within and between the grains. High values of critical current densities (Jc) in field (∼4× 105 A cm2 at 8 T and 4.2 K), extrapolated critical fields [Hc2 (0)] (>45 T), and slopes of critical field versus temperature (1.4 TK) are observed. Our results suggest that low growth temperatures (300 °C) and oxygen doping (0.65%) can produce MgB2 with high Jc values in field and Hc2 for high-field magnet applications.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)