Two-dimensional few electron systems in high magnetic fields: Composite-fermion or rotating-electron-molecule approach?

A new class of analytic and parameter-free, strongly correlated wave functions of simple functional form is derived for few electrons in two-dimensional quantum dots under high magnetic fields. These wave functions are constructed through breaking and subsequent restoration of the circular symmetry, and they offer a natural alternative to the Laughlin and composite-fermion functions. Underlying our approach is a collectively-rotating-electron-molecule picture. The angular momenta allowed by molecular symmetry correspond to the filling-factors' hierarchy of the fractional quantum Hall effect.