Simple and inexpensive technique for measuring the transition temperature of superconducting thick films from 60 to 300 K using liquid nitrogen and subcooled liquid oxygen

This paper describes a simple and low-cost experimental setup intended for AC susceptibility measurements between 60 and 300 K. A mutual inductance bridge for measuring the transition temperature of high-Tc superconductor thick films was constructed. The device is based on using liquid nitrogen and subcooled liquid oxygen; it allows temperatures down to 60 K to be achieved. Experimental details are described and illustrative measurements on high-Tc superconductor thick films are included.