Lüscher S, Heinzel T, Ensslin K, Wegscheider W, Bichler M
Solid State Physics Laboratory, ETH Zürich, Switzerland.
Phys Rev Lett. 2001 Mar 5;86(10):2118-21. doi: 10.1103/PhysRevLett.86.2118.
Coulomb blockade resonances are measured in a GaAs quantum dot in which both shape deformations and interactions are small. The parametric evolution of the Coulomb blockade peaks shows a pronounced pair correlation in both position and amplitude, which is interpreted as spin pairing. As a consequence, the nearest-neighbor distribution of peak spacings can be well approximated by a modified bimodal Wigner surmise, in which interactions are taken into account beyond the constant interaction model.
