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arXiv · 1402.1915

Enhanced spin-orbit interaction and Kondo scattering in $\delta$-doped LaTiO$_3$/SrTiO$_3$ interfaces

Shubhankar Das·A. Rastogi·Lijun Wu·Jin-Cheng Zheng·Z. Hossain·Yimei Zhu·R. C. Budhani
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Abstract

We present a study of delta ($\delta$) doping at LaTiO$_3$/SrTiO$_3$ (LTO/STO) interface with iso-structural antiferromagnetic perovskite LaCrO$_3$ (LCO) that dramatically alters the properties of the two dimensional electron gas (2-DEG) at the interface. The effects include a reduction in sheet-carrier density, prominence of the low temperature resistivity minimum, enhancement of weak antilocalization below 10 K and observation of a strong anisotropic magnetoresistance (MR). The positive and negative MR for out-of-plane and in-plane field respectively and the field and temperature dependencies of MR suggest Kondo scattering by localized Ti$^{3+}$ moments renormalized by spin-orbit interaction at T $<$ 10 K, with the increased $\delta$-layer thickness. Electron energy loss spectroscopy and density functional calculations provide convincing evidence for blocking of electron transfer from LTO to STO by the $\delta$-layer.

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Shubhankar Das, A. Rastogi, Lijun Wu, Jin-Cheng Zheng, Z. Hossain, Yimei Zhu, R. C. Budhani. 2014-02-09. Enhanced spin-orbit interaction and Kondo scattering in $\delta$-doped LaTiO$_3$/SrTiO$_3$ interfaces. https://doi.org/10.1103/physrevb.90.081107

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