摘要
Transition metals contain d-orbital electrons,and compounds based on transition metals often exhibit a duality of magnetism and superconductivity.To date,a large number of interesting physics phenomena exhibited by transition-metal compounds have been discovered;for example,high-temperature superconductivity has been found to emerge in compounds such as copper-oxide (cuprate)compounds,iron pnictides/chalcogenides.Understanding the relationship between superconductivity and magnetism is essential for realizing these unconventional superconductors.