Magnetic domain structure of colossal magnetoresistance thin films and islands

We synthesized 10–200 nm thick colossal magnetoresistive La0.7Sr0.3MnO3 (LSMO) thin films under compressive strain, resulting in perpendicular anisotropy. Similar magnetic domain structures in LSMO films thicker than 40 nm were observed by magnetic force microscopy and were also seen with photoemission electron microscopy. Recent transport measurements, in conjunction with this result, suggest a dead layer at the interface, not at the surface. When varying the temperature from below the Curie temperature TC to above, the magnetic domains disappeared. These domains nucleated uniformly across the film when the temperature was subsequently lowered, but their positions were unrelated to the initial domains or to surface defects.