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arXiv · 1103.4921

Optical Aharonov-Bohm Effect on Wigner Molecules in Type-II Semiconductor Quantum Dots

Rin Okuyama·Mikio Eto·Hiroyuki Hyuga
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Abstract

We theoretically examine the magnetoluminescence from a trion and a biexciton in a type-II semiconductor quantum dot, in which holes are confined inside the quantum dot and electrons are in a ring-shaped region surrounding the quantum dot. First, we show that two electrons in the trion and biexciton are strongly correlated to each other, forming a Wigner molecule: Since the relative motion of electrons is frozen, they behave as a composite particle whose mass and charge are twice those of a single electron. As a result, the energy of the trion and biexciton oscillates as a function of magnetic field with half the period of the single-electron Aharonov-Bohm oscillation. Next, we evaluate the photoluminescence. Both the peak position and peak height change discontinuously at the transition of the many-body ground state, implying a possible observation of the Wigner molecule by the optical experiment.

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Rin Okuyama, Mikio Eto, Hiroyuki Hyuga. 2011-04-20. Optical Aharonov-Bohm Effect on Wigner Molecules in Type-II Semiconductor Quantum Dots. https://doi.org/10.1103/physrevb.83.195311

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