Sandwich-type MgB2/MgO/MgB2Josephson junctions with Au or MgB2interconnection were fabricated using hybrid physical-chemical vapor deposited MgB2thin films and RF-magnetron-sputtered MgO barrier. The junctions show properties similar to those in high-JcNb junctions with Jcup to 275kA/cm2at 4 K, which remains nonzero up to 40 K. Critical current modulations by applied magnetic field and constant voltage steps under microwave radiation were observed. Combined with the larger energy gaps in MgB2than in Nb, the junctions presented here allow simple MgB2digital circuits to work over 20 K or with a clock speed above 1 THz.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)