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arXiv · 0905.3589

Particle-Hole Symmetry Breaking and the 5/2 Fractional Quantum Hall Effect

Hao Wang·D. N. Sheng·F. D. M. Haldane
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Abstract

We report on the study of the fractional quantum Hall effect at the filling factor 5/2 using exact diagonalization method with torus geometry. The particle-hole symmetry breaking effect is considered using an additional three-body interaction. Both Pfaffian and anti-Pfaffian states can be the ground state depending on the sign of the three-body interaction. The results of the low-energy spectrum, the wave function overlap, and the particle-hole parity evolution, have shown the clear evidence of a direct sharp transition (possibly first-order) from the Pfaffian to the anti-Pfaffian state at the Coulomb point. A quantum phase diagram is established, where one finds further transitions from the Pfaffian or anti-Pfaffian state to the nearby compressible phases induced by a change of the pseudopotential.

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Hao Wang, D. N. Sheng, F. D. M. Haldane. 2009-05-22. Particle-Hole Symmetry Breaking and the 5/2 Fractional Quantum Hall Effect. https://doi.org/10.1103/physrevb.80.241311

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