Cluster glass induced unconventional exchange bias in epitaxial LaMnO3/SrMnO3 bilayers

Abstract Unconventional exchange bias (EB) has been observed in epitaxially grown manganite bilayers composed of ferromagnetic LaMnO 3 and G-type antiferromagnetic SrMnO 3 , with the Curie temperature T C of LaMnO 3 lower than the Neel temperature T N of SrMnO 3 . A maximum EB field of 254 Oe at 2 K is achieved and the unconventional EB appears below a blocking temperature of about 150 K, very close to the T C of the LaMnO 3 layer. Such an effect is believed to arise from an interfacial cluster-glass-like state due to the spin frustration at the interface in the LaMnO 3 /SrMnO 3 bilayer.