Observation of step-induced magnetic domain formation in La_(1-x)Sr_xMnO_3 thin films by photoelectron emission microscopy

摘要

Magnetic domain formation in thin films of La_(1-x)Sr_xMnO_3 (LSMO) with x=0.2 and 0.4 epitaxially grown on stepped SrTiO_3 (001) substrates has been investigated by photoelectron emission microscopy. The magnetic domains show a stripe structure elongated along the step directions, indicating uniaxial magnetic anisotropy induced by step structures. We have also found that the magnetization of the magnetic domains is slightly meandering at domain boundaries. The existence of the additional structures suggests that the magnetic domains in LSMO films are also influenced by biaxial magnetocrystalline anisotropy. The direct observation of the magnetic domain structures suggests that the competition between the two magnetic anisotropies may play an important role in magnetic properties in LSMO films.