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What happens to superconductivity when a material is warmed above its transition temperature?

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Figure 1: Specific heat in the normal (Cen) and superconducting (Ces) states of a classic superconductor as a function of absolute temperature. The two functions are identical at the transition temperature (Tc) and above Tc. — superconductivity Figure 1: Specific heat in the normal (C_en) and superconducting (C_es) states of a classic superconductor as a function of absolute temperature. The two functions are identical at the transition temperature (T_c) and above T_c.

When a material is warmed above its transition temperature ( $T_{c}$ ), it loses its superconducting properties and reverts to a normal, nonsuperconducting state.123

In the superconducting state, conduction electrons form ordered pairs known as Cooper pairs, which allow electric current to flow with zero resistance. As the temperature approaches $T_{c}$ , the energy gap associated with this ordering decreases, and the number of thermally excited electrons increases. Once the material exceeds its transition temperature, this ordering is disrupted, and the material regains its electrical resistance, behaving like a normal conductor.45612

Additionally, the Meissner effect—the expulsion of magnetic fields from the interior of the material—ceases to occur once the material transitions out of the superconducting state.1