Observation of giant anomalous Ettingshausen effect in permanent magnets.

A potential of permanent magnets as thermoelectric converters is uncovered. It is found that a SmCo$_5$-type magnet exhibits the giant anomalous Ettingshausen effect (AEE) at room temperature and its charge-to-heat current conversion coefficient is more than one order of magnitude greater than that of typical ferromagnetic metals. The giant AEE is an exclusive feature of the SmCo$_5$-type magnet among various permanent magnets in practical use, which is independent of the conventional performance of magnets based on static magnetic properties. The experimental results show that the giant AEE originates from the intrinsic transverse thermoelectric conductivity of SmCo$_5$. This finding makes a connection between permanent magnets and thermal energy engineering, providing the basis for creating "thermoelectric permanent magnets".