Superconductivity and superconductors have always been the most attractive topic in condensed matter physics for one century,while magnetoelectricity and multiferroics have become another emergent hotspot since 2003.Both these two fields are not only physical meaningful to understand the correlated electrons in solids,but also technological important for applications.In early years,magnetism was widely believed to contradict superconductivity.But in cuprates,iron-pnictides,and iron-chalcogenides,magnetism plays a crucial role to induce superconductivity[1-4].As a contrast,magnetism was thought to contradict ferroelectricity[5],but in recently found type-Ⅱ multiferroics,particular magnetism can induce ferroelectric polarization (P)[6-7].Thus,magnetism plays as a common ingredient in both high-temperature superconductors and type-Ⅱ multiferroics,and may link these two branches of correlated electrons.