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arXiv · 0809.1362

Observation of excited states in a p-type GaAs quantum dot

Y. Komijani·M. Csontos·T. Ihn·K. Ensslin·D. Reuter·A. D. Wieck
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Abstract

A quantum dot fabricated by scanning probe oxidation lithography on a p-type, C-doped GaAs/AlGaAs heterostructure is investigated by low temperature electrical conductance measurements. Clear Coulomb blockade oscillations are observed and analyzed in terms of sequential tunneling through the single-particle levels of the dot at T_hole = 185 mK. The charging energies as large as 2 meV evaluated from Coulomb diamond measurements together with the well resolved single-hole excited state lines in the charge stability diagram indicate that the dot is operated with a small number of confined particles close to the ultimate single-hole regime.

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Y. Komijani, M. Csontos, T. Ihn, K. Ensslin, D. Reuter, A. D. Wieck. 2008-09-08. Observation of excited states in a p-type GaAs quantum dot. https://doi.org/10.1209/0295-5075/84/57004

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