Oscillatory exchange bias effect in La_0.67Sr_0.33MnO₃/G-SrMnO₃/La_0.67Sr_0.33MnO₃ sandwiches

Abstract

Abstract We investigate the exchange bias effect in La 0.67 Sr 0.33 MnO 3 / G -SrMnO 3 / La 0.67 Sr 0.33 MnO 3 (LSMO/SMO/LSMO) sandwiches, where the spacer is a G -type antiferromagnet. Because of the cycloid bulk spins in the SMO modulated by the top LSMO layer, the sandwich structure exhibits an oscillatory exchange bias behavior as a function of the SMO thickness. This unprecedented phenomenon vanishes in LSMO/SMO bilayers, where the exchange bias saturates as the SMO thickness increases, giving rise to the antiferromagnetic anisotropy constant of SMO, 1.0 –2.0 × 10 5 erg cm −3 . The results provide a broad opportunity to tailor antiferromagnetic moments by interfacial design for antiferromagnet spintronics.