Spectroscopy of Quantum-Dot Orbitals with In-Plane Magnetic Fields

ORAL

Abstract

While spins in quantum dots have received a lot of attention for the development as a qubit, the orbitals which are hosting the qubit have largely been ignored. However, important processes such as electric-dipole spin resonance and spin relaxation depend sensitively on the dot shape due to the anisotropic nature of the spin-orbit interaction.
Here, we present a method which allows quantifying the in-plane orientation angle and the strength of the hard confinement perpendicular to the 2D gas in which the gate-defined single-electron GaAs dot is formed. Using a piezo electric rotator, we control the direction of the magnetic field in the 2D plane and measure the in-plane orbital energies using pulse gate spectroscopy. Based on a model of the orbitals, we extract the orientation angle of the dot in the 2D plane, quantify the strong confinement and characterize deviations from a harmonic oscillator potential. Our measurements demonstrate a versatile tool for quantum dots with one dominant axis of strong confinement.

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Presenters

  • Leon Camenzind

    University of Basel, Department of Physics, University of Basel

Authors

  • Leon Camenzind

    University of Basel, Department of Physics, University of Basel

  • Liuqi Yu

    Laboratory for Physical Sciences, College Park, MD, University of Basel, Department of Physics, University of Basel

  • Peter Stano

    Center for Emergent Matter Science, RIKEN

  • Jeramy D. Zimmerman

    Materials Department, UC Santa Barbara

  • Arthur C Gossard

    Materials Department, UC Santa Barbara, University of California, Santa Barbara

  • Daniel Loss

    University of Basel, Department of Physics, University of Basel

  • Dominik Zumbuhl

    University of Basel, Department of Physics, Univ of Basel, University of Basel, Department of Physics, Department of Physics, University of Basel, Physics, University of Basel