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arXiv · 2001.04894

Electrostatic potential mapping at ferroelectric domain walls by low-temperature photoemission electron microscopy

J. Schaab·K. Shapovalov·P. Schoenherr·J. Hackl·M. I. Khan·M. Hentschel·Z. Yan·E. Bourret·C. M. Schneider·S. Nemsák·M. Stengel·A. Cano·D. Meier
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Abstract

Low-temperature X-ray photoemission electron microscopy (X-PEEM) is used to measure the electric potential at domain walls in improper ferroelectric Er0.99Ca0.01MnO3. By combining X-PEEM with scanning probe microscopy and theory, we develop a model that relates the detected X-PEEM contrast to the emergence of uncompensated bound charges, explaining the image formation based on intrinsic electronic domain-wall properties. In contrast to previously applied low-temperature electrostatic force microscopy (EFM), X-PEEM readily distinguishes between positive and negative bound charges at domain walls. Our study introduces an X-PEEM based approach for low-temperature electrostatic potential mapping, facilitating nanoscale spatial resolution and data acquisition times in the order of 0.1-1 sec.

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J. Schaab, K. Shapovalov, P. Schoenherr, J. Hackl, M. I. Khan, M. Hentschel, Z. Yan, E. Bourret, C. M. Schneider, S. Nemsák, M. Stengel, A. Cano, D. Meier. 2020-01-14. Electrostatic potential mapping at ferroelectric domain walls by low-temperature photoemission electron microscopy. https://doi.org/10.1063/1.5117881

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