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arXiv · 1804.00162

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

Leon C. Camenzind·Liuqi Yu·Peter Stano·Jeramy Zimmerman·Arthur C. Gossard·Daniel Loss·Dominik M. Zumbühl
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Abstract

We show that in-plane-magnetic-field assisted spectroscopy allows extraction of the in-plane orientation and full 3D shape of the quantum mechanical orbitals of a single electron GaAs lateral quantum dot with sub-nm precision. The method is based on measuring orbital energies in a magnetic field with various strengths and orientations in the plane of the 2D electron gas. As a result, we deduce the microscopic quantum dot confinement potential landscape, and quantify the degree by which it differs from a harmonic oscillator potential. The spectroscopy is used to validate shape manipulation with gate voltages, agreeing with expectations from the gate layout. Our measurements demonstrate a versatile tool for quantum dots with one dominant axis of strong confinement.

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Leon C. Camenzind, Liuqi Yu, Peter Stano, Jeramy Zimmerman, Arthur C. Gossard, Daniel Loss, Dominik M. Zumbühl. 2018-03-31. Spectroscopy of Quantum-Dot Orbitals with In-Plane Magnetic Fields. https://doi.org/10.1103/physrevlett.122.207701

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