Spin-Density-Functional Theory of Circular and Elliptical Quantum Dots
نویسندگان
چکیده
Using spin-density-functional theory, we study the electronic states of a two-dimensional parabolic quantum dot with up to N = 58 electrons. We observe a shell structure for the filling of the dot with electrons. Hund’s rule determines the spin configuration of the ground state, but only up to 22 electrons. At specific N , the ground state is degenerate, and a small elliptical deformation of the external potential induces a rotational charge-density-wave (CDW) state. Previously identified spin-density-wave (SDW) states are shown to be artifacts of broken spin symmetry in density-functional theory. PACS numbers: 73.23.-b, 73.23.Hk, 73.61.-r
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