Scaling analyses on the critical current density in MgB2/NbN/Si thin film

Abstract

Abstract Scaling analyses are performed on the critical current density J c in MgB2/NbN/Si thin film. In our previous work on MgB2/SiC/Si film [Mat. Sci. Eng. 502 (2019) 012184], we have shown that J c data well scale on a single line with the reduced scaling formula more than 10 orders of magnitude. We extend these studies onto MgB2 film with NbN buffer layer in comparison with SiC buffer. Experimental J c data under perpendicular magnetic field to the film are reduced against transition temperature and critical field, and applicability of the comprehensive scaling formula is examined over 16 orders of magnitude. Our scaling formula is revealed to be well applicable to the NbN-buffered film as well.