Gate-tuned Anomalous Hall Effect Driven by Rashba Splitting in Intermixed LaAlO3/GdTiO3/SrTiO3

arXiv (Cornell University)

Abstract

The Anomalous Hall Effect (AHE) is an important quantity in determining the properties and understanding the behavior of the two-dimensional electron system forming at the interface of SrTiO3-based oxide heterostructures. The occurrence of AHE is often interpreted as a signature of ferromagnetism, but it is becoming more and more clear that also paramagnets may contribute to AHE. We studied the influence of magnetic ions by measuring intermixed LaAlO3/GdTiO3/SrTiO3 at temperatures below 10 K. We find that, as function of gate voltage, the system undergoes a Lifshitz transition, while at the same time an onset of AHE is observed. However, we do not observe clear signs of ferromagnetism. We argue the AHE to be due to the change in Rashba spin-orbit coupling at the Lifshitz transition and conclude that also paramagnetic moments which are easily polarizable at low temperatures and high magnetic filds lead to the presence of AHE, which needs to be taken into account when extracting carrier densities and mobilities.

Authors 8

1. Martin Stehno

   University of Würzburg

   Affiliation as printed

   Physikalisches Institut (EP 3) , Universitt Wrzburg , Am Hubland 97074 Wrzburg , Germany

   Physikalisches Institut (EP 3), Universität Würzburg, Am Hubland 97074 Würzburg, Germany

2. Abhimanyu Rana

   BML Munjal University · University of Twente

   Affiliation as printed

   Center for Advanced Materials and Devices , BML Munjal University (Hero Group) , Gurgaon , India -122413

   MESA+ Institute for Nanotechnology , University of Twente , P.O. Box 217 , 7500 AE Enschede , The Netherlands

   Center for Advanced Materials and Devices, BML Munjal University (Hero Group), Gurgaon, 122413, India

3. Pim Reith

   University of Twente

   Affiliation as printed

   MESA+ Institute for Nanotechnology , University of Twente , P.O. Box 217 , 7500 AE Enschede , The Netherlands

   MESA+ Institute for Nanotechnology; University of Twente; P. O. Box 217 7500 AE Enschede The Netherlands

4. Nicolas Gauquelin

   University of Antwerp

   Affiliation as printed

   Electron Microscopy for Materials Science , University of Antwerp , Campus Groenenborger Groenenborgerlaan 171 , 2020 Antwerpen , Belgium

   Electron Microscopy for Materials Science, University of Antwerp, Campus Groenenborger Groenenborgerlaan 171, 2020 Antwerpen, Belgium

5. Johan Verbeeck

   University of Antwerp

   Affiliation as printed

   Electron Microscopy for Materials Science , University of Antwerp , Campus Groenenborger Groenenborgerlaan 171 , 2020 Antwerpen , Belgium

   Electron Microscopy for Materials Science, University of Antwerp, Campus Groenenborger Groenenborgerlaan 171, 2020 Antwerpen, Belgium

6. Hans Hilgenkamp

   University of Twente

   Affiliation as printed

   MESA+ Institute for Nanotechnology , University of Twente , P.O. Box 217 , 7500 AE Enschede , The Netherlands

   MESA+ Institute for Nanotechnology; University of Twente; P. O. Box 217 7500 AE Enschede The Netherlands

7. Alexander Brinkman

   University of Twente

   Affiliation as printed

   MESA+ Institute for Nanotechnology , University of Twente , P.O. Box 217 , 7500 AE Enschede , The Netherlands

   MESA+ Institute for Nanotechnology; University of Twente; P. O. Box 217 7500 AE Enschede The Netherlands

8. J. Aarts Aachen Kamerlingh Onnes Laboratory

   Leiden University

   Affiliation as printed

   Kamerlingh Onnes Laboratory , Leiden University , P.O. Box 9504 , 2300 RA Leiden , The Netherlands

   Kamerlingh-Onnes Laboratory, Leiden University, P.O.Box 9504, 2300 RA, Leiden, the Netherlands