Room-temperature giant magnetotranstance effect in single-phase multiferroics

Single-phase multiferroic materials are usually considered useless because of the weak magnetoelectric effects,low operating temperature,and small electric polarization induced by magnetic orders.As a result,current studies on applications of the magnetoelectric effects are mainly focusing on multiferroic heterostructures and composites.Here we report a room-temperature giant effect in response to external magnetic fields in single-phase multiferroics.A low magnetic field of 1000 Oe applied on the spin-driven multiferroic hexaferrites BaSrCo;Fe;AlO;and Ba;Sr;Co;Fe;AlO;is able to cause a huge change in the linear magnetoelectric coefficient（α;=dE/dH） by several orders,leading to a giant magnetotranstance（GMT） effect at room temperature.The GMT effect is comparable to the well-known giant magnetoresistance（GMR） effect in magnetic multilayers,and thus opens up a door toward practical applications for single-phase multiferroics.