Electrostatic modulation of periodic potentials in a two-dimensional electron gas: from antidot lattice to quantum dot lattice

ORAL

Abstract

We use a dual gated device structure to introduce a gate-tunable periodic potential in a GaAs/AlGaAs two dimensional electron gas (2DEG). Using a suitable choice of gate voltages we can controllably alter the potential landscape in the 2DEG, thereby inducing either a periodic array of antidots or quantum dots. Antidots are artificial scattering centers, and therefore allow for a study of electron dynamics. On the other hand, a quantum dot lattice provides the opportunity to study correlated electron physics. We use a variety of electrical measurements such as magneto-resistance, thermo-voltage and current-voltage characteristics to probe these two contrasting regimes.

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Authors

  • Srijit Goswami

    Department of Physics, Indian Institute of Science

  • Mohammad Ali Aamir

    Department of Physics, Indian Institute of Science

  • Saquib Shamim

    Department of Physics, Indian Institute of Science

  • Christoph Siegert

    Cavendish Laboratory, University of Cambridge

  • Michael Pepper

    Department of Electronic and Electrical Engineering, University College London

  • Ian Farrer

    Cavendish Laboratory, University of Cambridge, J.J.Thomson Avenue, Cambridge; UK, Cavendish Laboratory, University of Cambridge, Cavendish Laboratory, Cambridge University, J. J. Thomson Avenue, Cambridge, CB3 0HE, UK, University of Cambridge

  • Dave Ritchie

    Cavendish Laboratory, University of Cambridge, J.J.Thomson Avenue, Cambridge; UK, Cavendish Laboratory, University of Cambridge, Cavendish Laboratory, Cambridge University, J. J. Thomson Avenue, Cambridge, CB3 0HE, UK, University of Cambridge

  • Arindam Ghosh

    Indian Institute of Science, Bangalore, Department of Physics, Indian Institute of Science, Bangalore, Department of Physics, Indian Institute of Science