We report Aharonov-Bohm (AB)-type quantum interference in simply-connected devices created at the LaAlO3/SrTiO3 interface using conductive-atomic force microscope (c-AFM) lithography. The oscillations are multi-periodic functions of magnetic field strength, and they exhibit a substantial magnetic hysteresis with frequencies that depends on the magnetic sweep direction. The oscillation amplitude for the lowest two frequencies approaches e2/h, consistent with the theoretical maximum for the AB effect, and harmonics up to third order are observable. Broadband quasiperiodic behavior is reported in a fraction of simply-connected electron waveguide devices that exhibit magnetic asymmetries. Curiously, nanoscale ring devices that are multiply-connected lack signatures of AB quantum interference. The interference phenomena are associated with an inhomogeneous magnetic landscape within the LaAlO3/SrTiO3 nanostructures.
@article{arxiv.1909.11259,
title = {Strong Aharonov-Bohm quantum interference in simply-connected LaAlO$_3$/SrTiO$_3$ structures},
author = {Patrick Irvin and Hyungwoo Lee and Jung-Woo Lee and Megan Briggeman and Shicheng Liu and Anil Annadi and Guanglei Cheng and Michelle Tomczyk and Jinanan Li and Mengchen Huang and Chang-Beom Eom and Jeremy Levy},
journal= {arXiv preprint arXiv:1909.11259},
year = {2019}
}