Mechanism of high-temp. superconductors

[raldenorsful]

My prof. asked: "What is the mechanism that causes certain materials to exhibit superconductivity at temperatures much higher than around 25 kelvin?"
then until now it remain a question to me?.. so anyone have an idea? thank you.

 

[Enthalpy]

This is still an open question, so why should your prof ask if he ignores the answer? The best answer is "not BCS".