Use of liquid nitrogen and liquid helium in superconductivity studies

Even though these materials have transition temperatures (Tc) values above 4.2 K, it is general practice to cool them to 4.2 K during operation. Reasons for doing so are following: 4.2 K is the B. Pt of LHe. It is straightforward to design a cryostat operating at only one temperature i.e. the B.Pt. of LHe. Practical enhancement that occurs in Jc values while operating at 4.2 K (even up to 50%). Operating at 4.2 K allows a higher magnetic field to be achieved in the magnet. In this paper, the authors show how LN2 and LHe are used in superconductivity studies and we restrict our study to the following: Production LN2 and LHe (briefly); Mechanical and Thermal design data while using LN2 and LHe; General aspects of cryostat design; Use of LN2 and LHe in the lab-precautions, safety aspects etc