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Title: Correlating Polar Distortions and Interfacial Charge at the Polar/Non-polar LaCrO$_3$/SrTiO$_3$ (001) Interface
The relationship between the sheet carrier concentration, $n_s$, of LaCrO$_3$(LCO)/SrTiO$_3$(STO) heterostructures and their structural properties has been investigated. Under low oxygen partial pressure, the STO substrate is reduced during growth as evidenced by a high $n_s$ of 10$^{16}$ cm$^{-2}$. By controlling the post-growth annealing conditions, heterostructures with $n_s$ of 10$^{13}$-10$^{16}$ cm$^{-2}$ are achieved. The atomic-scale structure of the samples are obtained using high-resolution synchrotron X-ray diffraction measurements. For heterostructures with $n_s$ at or below 3$\times 10^{13}$ cm$^{-2}$, polar distortions are present within the LCO layers and increase in magnitude with decreasing sheet carrier concentration. These distortions are absent for samples with $n_s$ on the order of 10$^{15}$-10$^{16}$ cm$^{-2}$ where interfacial carriers play a role in alleviating the polar discontinuity at the LCO/STO interface. These results suggest that interfacial charge carriers and polar distortions can act as complementary mechanisms to alleviate the polar discontinuity at polar/non-polar complex oxide interfaces.  more » « less
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AIP advances
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Medium: X
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National Science Foundation
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