%0 Journal Article
%T Magnetic Field Dependence of the Level Spacing of a Small Electron Droplet
%A O. Klein
%A D. Goldhaber-Gordon
%A C. de C. Chamon
%A M. A. Kastner
%J Physics
%D 1995
%I arXiv
%R 10.1103/PhysRevB.53.R4221
%X The temperature dependence of conductance resonances is used to measure the evolution with the magnetic field of the average level spacing $\Delta\epsilon$ of a droplet containing $\sim 30$ electrons created by lateral confinement of a two-dimensional electron gas in GaAs. $\Delta\epsilon$ becomes very small ($< 30\mu$eV) near two critical magnetic fields at which the symmetry of the droplet changes and these decreases of $\Delta\epsilon$ are predicted by Hartree-Fock (HF) for charge excitations. Between the two critical fields, however, the largest measured $\Delta\epsilon= 100\mu$eV is an order of magnitude smaller than predicted by HF but comparable to the Zeeman splitting at this field, which suggests that the spin degrees of freedom are important. PACS: 73.20.Dx, 73.20.Mf
%U http://arxiv.org/abs/cond-mat/9511133v1