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Transition from quantum Hall to compressible states in the second Landau level: new light on the $ν$=5/2 enigma

Rudolf H. Morf
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Abstract

Quantum Hall states at filling fraction $ν$=5/2 are examined by numerical diagonalization. Spin-polarized and -unpolarized states of systems with $N\le 18$ electrons are studied, neglecting effects of Landau level mixing. We find that the ground state is spin polarized. It is incompressible and has a large overlap with paired states like the Pfaffian. For a given sample, the energy gap is about 11 times smaller than at $ν$=1/3. Evidence is presented of phase transitions to compressible states, driven by the interaction strength at short distance. A reinterpretation of experiments is suggested.

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Rudolf H. Morf. 1998-09-01. Transition from quantum Hall to compressible states in the second Landau level: new light on the $ν$=5/2 enigma. https://doi.org/10.1103/physrevlett.80.1505

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