Fractional quantum hall effect and electron correlations in partially filled first excited Landau level

We present a quantitative study of most prominent incompressible quantum Hall states in the partially filled first excited Landau level (LL1) which have been recently studied experimentally by Choi et al. The pseudopotential describing the electron–electron interaction in LL1 is harmonic at short range. It produces a series of incompressible states which is different from its LL0 counterpart. The numerical data indicate that the most prominent states View the MathML source, View the MathML source and View the MathML source are not produced by Laughlin correlated electrons, but result from a tendency of electrons to form pairs or larger clusters which eventually become Laughlin correlated. States with smaller gaps at filling factors View the MathML source, View the MathML source, View the MathML source, View the MathML source are Laughlin correlated electron or hole states and fit Jainʹs sequence of filled CF4 levels.