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HL: Fachverband Halbleiterphysik
HL 29: Quantum Transport and Quantum Hall Effects
HL 29.8: Talk
Wednesday, March 20, 2024, 11:45–12:00, EW 561
Giant Negative Magnetoresistance as a Function of the Electron Density — •Lina Bockhorn1, Dieter Schuh2, Christian Reichl3, Werner Wegscheider3, and Rolf J. Haug1 — 1Institut für Festkörperphysik, Leibniz Universität Hannover, Germany — 2Institut für Experimentelle und Angewandte Physik, Universität Regensburg, Germany — 3Laboratorium für Festkörperphysik, ETH Zürich, Switzerland
Ultra-high mobility two-dimensional electron gases not only show an increasing number of new fractional filling factors, but also an astonishing robust negative magnetoresistance at zero magnetic field [1 -4]. In-situ variation of the electron density enables a deep insight into the nature of the negative magnetoresistance. Here, we investigate the temperature-dependent giant negative magnetoresistance (GNMR) as a function of the electron density for several temperatures and currents. For low densities, the temperature dependence of the GNMR is described by the electron-electron interaction correction to the conductivity considering mixed disorder [5]. In the case of higher electron densities, a non-linear current dependence is observed which has to be described within the hydrodynamic regime [6].
[1] L. Bockhorn et al., Phys. Rev. B 83, 113301 (2011).
[2] A. T. Hatke et al., Phys. Rev. B 85, 081304 (2012).
[3] L. Bockhorn et al., Phys. Rev. B 90, 165434 (2014).
[4] L. Bockhorn et al., Appl. Phys. Lett. 108, 092103 (2016).
[5] I. V. Gornyi et al., Phys. Rev. B. 69, 045313 (2004).
[6] P. S. Alekseev, Phys. Rev. Lett. 117, 166601, (2016).
Keywords: Giant Negative Magnetoresistance; electron-electron interaction correction; hydrodynamic; Ultra-high mobility two-dimensional electron gases