Magnetoresistance oscillations and relaxation effects at the SrTiO3-LaAlO3 interface

M. van Zalk; J. Huijben; A. J. M. Giesbers; M. Huijben; U. Zeitler; J. C. Maan; W. G. van der Wiel; G. Rijnders; D. H. A. Blank; H. Hilgenkamp; A. Brinkman

arXiv · 0806.4450

Magnetoresistance oscillations and relaxation effects at the SrTiO3-LaAlO3 interface

M. van Zalk·J. Huijben·A. J. M. Giesbers·M. Huijben·U. Zeitler·J. C. Maan·W. G. van der Wiel·G. Rijnders·D. H. A. Blank·H. Hilgenkamp·A. Brinkman

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Abstract

We present low-temperature and high-field magnetotransport data on SrTiO3-LaAlO3 interfaces. The resistance shows hysteresis in magnetic field and a logarithmic relaxation as a function of time. Oscillations in the magnetoresistance are observed, showing a square root periodicity in the applied magnetic field, both in large-area unstructured samples as well as in a structured sample. An explanation in terms of a commensurability condition of edge states in a highly mobile two-dimensional electron gas between substrate step edges is suggested.

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M. van Zalk, J. Huijben, A. J. M. Giesbers, M. Huijben, U. Zeitler, J. C. Maan, W. G. van der Wiel, G. Rijnders, D. H. A. Blank, H. Hilgenkamp, A. Brinkman. 2008-06-27. Magnetoresistance oscillations and relaxation effects at the SrTiO3-LaAlO3 interface. https://arxiv.org/abs/0806.4450

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