Induced ferromagnetism and antiferromagnetism in perovskite quantum wells

We report on induced magnetism in thin SrTiO$_{3}$ quantum wells embedded in ferrimagnetic GdTiO$_{3}$ and antiferromagnetic SmTiO$_{3}$, respectively. The SrTiO$_{3}$ quantum wells contain a high density of mobile electrons (7x10$^{14}$ cm$^{-2})$. We show that the longitudinal and transverse magnetoresistance in the structures with GdTiO$_{3}$ are consistent with anisotropic magnetoresistance, and thus indicative of induced ferromagnetism in the SrTiO$_{3}$. Measurements of the sheet and Hall resistances as a function of temperature in the structures with SmTiO$_{3}$ are consistent with two-dimensional itinerant antiferromagnetism induced in the SrTiO$_{3}$ layer as a result of the confinement of an extreme charge density coupled with proximity affects from the neighboring SmTiO$_{3}$. The studies show that the properties of thin SrTiO$_{3}$ quantum wells can be tuned to obtain magnetic states that do not exist in the bulk material.