Silsbee's rule - transition between superconducting and normal (resistive) state due to hard superconductor). The value of Hc denotes critical magnetic field. There are two values of critical field. The region between Hc1 and Hc2 is a mixed state (vortex state). (H - magnetic field, M - magnetisation).
After: Preeti Maheshwari, Electronic Components and Processes, New Age International, 2006, ISBN 9788122417944, p. 119-120
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