Evolution of ferromagnetism in two-dimensional electron gas of LaTiO3/SrTiO3*

Despite almost one-decade-long research effort, the microscopic origin of ferromagnetism in LaAlO3/SrTiO3 is still an open question. Here we report the antiferromagnetic affected two-dimensional electron gas (2DEG) on the interface between antiferromagnetic Mott insulator LaAlO3 and non-magnetic band insulator SrTiO3. The clear two-dimensional reflection high-energy electron diffraction (RHEED) pattern and X-ray photoelectron spectroscopy confirm the crystal structure and chemical composition, while the negative correlation between temperature and resistivity in low temperature shows the existence of magnetic islands. The observation of clear hysteresis in magnetotransport at low magnetic fields (~ 2 T) shows the effect of canted magnetic islands in the hole-rich LaAlO3 near the interface. Our result provides another path for designing all-oxide structures and is relevant to spintronics applications.