Electric Field Control of Chirality

Piush Behera; Molly A. May; Fernando Gómez-Ortiz; Sandhya Susarla; Sujit Das; Christopher T. Nelson; Lucas Caretta; Shang-Lin Hsu; Margaret R. McCarter; Benjamin H. Savitzky; Edward S. Barnard; Archana Raja; Zijian Hong; Pablo García-Fernandez; Stephen W. Lovesey; Gerrit van der Laan; Colin Ophus; Lane W. Martin; Javier Junquera; Markus B. Raschke; Ramamoorthy Ramesh

arXiv · 2105.14109

Electric Field Control of Chirality

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Abstract

Polar textures have attracted significant attention in recent years as a promising analog to spin-based textures in ferromagnets. Here, using optical second harmonic generation based circular dichroism, we demonstrate deterministic and reversible control of chirality over mesoscale regions in ferroelectric vortices using an applied electric field. The microscopic origins of the chirality, the pathway during the switching, and the mechanism for electric-field control are described theoretically via phase-field modeling and second-principles simulations, and experimentally by examination of the microscopic response of the vortices under an applied field. The emergence of chirality from the combination of non-chiral materials and subsequent control of the handedness with an electric field has far-reaching implications for new electronics based on chirality as a field controllable order parameter.

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Piush Behera, Molly A. May, Fernando Gómez-Ortiz, Sandhya Susarla, Sujit Das, Christopher T. Nelson, Lucas Caretta, Shang-Lin Hsu, Margaret R. McCarter, Benjamin H. Savitzky, Edward S. Barnard, Archana Raja, Zijian Hong, Pablo García-Fernandez, Stephen W. Lovesey, Gerrit van der Laan, Colin Ophus, Lane W. Martin, Javier Junquera, Markus B. Raschke, Ramamoorthy Ramesh. 2021-05-28. Electric Field Control of Chirality. https://arxiv.org/abs/2105.14109

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