Electron states in a double quantum dot with broken axial symmetry

Abstract

We study theoretically the electron states in a system of two vertically stacked quantum dots. We investigate the influence of the geometrical symmetry breaking (caused by the displacement as well as the ellipticity of the dots) on the electron states. Our modeling is based on the 8-band kp method. We show that the absence of axial symmetry of the system leads to a coupling of the s state from one dot with the p and d states from the other. Our findings indicate, that this coupling can produce a strong energy splitting at resonance (on the order of several meV) in the case of closely spaced quantum dots. Furthermore, we show that in the presence of a piezoelectric field, the direction of the displacement plays an important role in the character of the coupling.

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• Quantum dots as optimized chiral emitters for photonic integrated circuits
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• Single-particle and collective excitations in quantum wires comprised of vertically stacked quantum dots: Finite magnetic field
• Distributed Bragg reflector-mediated excitation of InAs/InP quantum dots emitting in the telecom C-band