Imaging orbital Rashba induced charge transport anisotropy

Eylon Persky; Xi Wang; Giacomo Sala; Thierry C. van Thiel; Edouard Lesne; Alexander Lau; Mario Cuoco; Marc Gabay; Carmine Ortix; Andrea D. Caviglia; Beena Kalisky

arXiv · 2502.09719

Imaging orbital Rashba induced charge transport anisotropy

Eylon Persky·Xi Wang·Giacomo Sala·Thierry C. van Thiel·Edouard Lesne·Alexander Lau·Mario Cuoco·Marc Gabay·Carmine Ortix·Andrea D. Caviglia·Beena Kalisky

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Abstract

Identifying orbital textures and their effects on the electronic properties of quantum materials is a critical element in developing orbitronic devices. However, orbital effects are often entangled with the spin degree of freedom, making it difficult to uniquely identify them in charge transport phenomena. Here, we present a combination of scanning superconducting quantum interference device (SQUID) current imaging, global transport measurements, and theoretical analysis, that reveals a direct contribution of orbital textures to the linear charge transport of 2D systems. Specifically, we show that in the LaAlO$_3$/SrTiO$_3$ interface, which lacks both rotation and inversion symmetries, an anisotropic orbital Rashba coupling leads to conductivity anisotropy in zero magnetic field. We experimentally demonstrate this result by locally measuring the conductivity anisotropy, and correlating its appearance to the non-linear Hall effect, showing that the two phenomena have a common origin. Our results lay the foundations for an all--electrical probing of orbital currents in two-dimensional systems.

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Eylon Persky, Xi Wang, Giacomo Sala, Thierry C. van Thiel, Edouard Lesne, Alexander Lau, Mario Cuoco, Marc Gabay, Carmine Ortix, Andrea D. Caviglia, Beena Kalisky. 2025-02-13. Imaging orbital Rashba induced charge transport anisotropy. https://arxiv.org/abs/2502.09719

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