Ground-state energy and Wigner crystallization in thick 2D-electron systems
arXiv:cond-mat/0508166 · doi:10.1103/PhysRevB.72.195315
Abstract
The ground state energy of the 2-D Wigner crystal is determined as a function of the thickness of the electron layer and the crystal structure. The method of evaluating the exchange-correlation energy is tested using known results for the infinitely-thin 2D system. Two methods, one based on the local-density approximation(LDA), and another based on the constant-density approximation (CDA) are established by comparing with quantum Monte-Carlo (QMC) results. The LDA and CDA estimates for the Wigner transition of the perfect 2D fluid are at and 32 respectively, compared with from QMC. For thick-2D layers as found in Hetero-junction-insulated-gate field-effect transistors, the LDA and CDA predictions of the Wigner transition are at and 15.5 respectively. Impurity effects are not considered here.
Last figure and Table are modified in the revised version. Conclusions regarding the Wigner transition in thick layers are modified in the revised version. Latex manuscript, four figures