FIG. 4. Expected behavior of a hypothetical "perfect conductor" in a magnetic field. (a)-(b) With no applied magnetic field, the sample is cooled to below its transition temperature Tc. The sample becomes resistanceless. (c) Because induced currents flow without resistance, the cooled sample is able to expel completely an applied magnetic field Ba that is less than Hc(T) in magnitude. (d) When the applied magnetic field Ba is removed, the sample has no residual magnetization. (e) With a magnetic field Ba applied, the sample is cooled below its transition temperature Tc. (f) The process of cooling does not induce currents in the "perfect conductor" so that the applied magnetic field Ba remains in the interior of the sample. (g) When the applied magnetic field Ba is removed, induced currents flow without resistance to maintain a magnetic field Ba throughout the interior of the sample. The sample is left with a net magnetization. The sample states depicted in (f) and (g) do not  correspond to the observed behavior of a superconductor.5
To Fig. 3

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