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arXiv · 1602.05597

Magnetic interactions at the nanoscale in trilayer titanates LaTiO$_3$/SrTiO$_3$/YTiO$_3$

Yanwei Cao·Zhenzhong Yang·M. Kareev·Xiaoran Liu·D. Meyers·S. Middey·D. Choudhury·P. Shafer·Jiandong Guo·J. W. Freeland·E. Arenholz·Lin Gu·J. Chakhalian
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Abstract

We report on the phase diagram of competing magnetic interactions at nanoscale in engineered ultra-thin trilayer heterostructures of LaTiO$_{3}$/SrTiO$_{3}$/YTiO$_{3}$, in which the interfacial inversion symmetry is explicitly broken. Combined atomic layer resolved scanning transmission electron microscopy with electron energy loss spectroscopy and electrical transport have confirmed the formation of a spatially separated two-dimensional electron liquid and high density two-dimensional localized magnetic moments at the LaTiO$_3$/SrTiO$_3$ and SrTiO$_3$/YTiO$_3$ interfaces, respectively. Resonant soft X-ray linear dichroism spectroscopy has demonstrated the presence of orbital polarization of the conductive LaTiO$_3$/SrTiO$_3$ and localized SrTiO$_3$/YTiO$_3$ electrons. Our results provide a route with prospects for exploring new magnetic interfaces, designing tunable two-dimensional $d$-electron Kondo lattice, and potential spin Hall applications.

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Yanwei Cao, Zhenzhong Yang, M. Kareev, Xiaoran Liu, D. Meyers, S. Middey, D. Choudhury, P. Shafer, Jiandong Guo, J. W. Freeland, E. Arenholz, Lin Gu, J. Chakhalian. 2016-02-17. Magnetic interactions at the nanoscale in trilayer titanates LaTiO$_3$/SrTiO$_3$/YTiO$_3$. https://doi.org/10.1103/physrevlett.116.076802

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