Superconductivity magnetization hysteresis

Figure 8 Partial magnetization hysteresis loop at 5 K for a superconducting YE Cu O g single crystal. The solid triangles represent the response to increasing fields while the open triangles are for decreasing fields.

Figure 10 Comparison of partial magnetization hysteresis loops at 30 and 77 K for a superconducting T Ca j Ba2Cu20o single crystal (Tc is 105 K). The lack of hysteresis at 77 K is due to weak flux pinning.

Luh72] Luhman, T.S., Taggart, R., and Polo-nis, D.H., Magnetic Hysteresis Studies of Superconducting Beta Stabilized Titanium Alloys, Scr. Metall., Vol 6,1972, p. 1055-1060... 

External fields must be shielded to about 10-7T, i.e. well below earth magnetic field ( 50 jlT). The maximum recommended field is 10 6T and the dTc/dH (about lOOK/Tesla) is supplied around H = 0. The maximum power which may be supplied to the coils is between 10-9 and 10-1°W. The sweep rate used to trace out the superconducting transitions should be less than O.lmK/min (for W and Be) to avoid hysteresis effects. Unfortunately, nowadays SRM-767a and SRM-768 are no longer produced. 

The magnetic properties of the different MLPs were studied by using a superconducting quantum interference device (SQUID). Hysteresis loop of the samples were registered at temperature of 2... 

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