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arXiv · 0807.0638

Spontaneous Particle-Hole Symmetry Breaking in the $ν=5/2$ Fractional Quantum Hall Effect

Michael R. Peterson·Kwon Park·S. Das Sarma
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Abstract

The essence of the $ν=5/2$ fractional quantum Hall effect is believed to be well captured by the Moore-Read Pfaffian (or anti-Pfaffian) description. However, an important mystery regarding the formation of the Pfaffian state is the role of the three-body interaction Hamiltonian $H_3$ that produces the Pfaffian as an exact ground state and the concomitant particle-hole symmetry breaking. We show that a two-body interaction Hamiltonian $H_2$ constructed via particle-hole symmetrization of $H_3$ produces a ground state nearly exactly approximating the Pfaffian and anti-Pfaffian states, respectively, in the spherical geometry. More importantly, the ground state energy of $H_2$ is shown to exhibit a ``Mexican-hat'' structure as a function of particle number in the vicinity of half filling for a given flux indicating spontaneous particle-hole symmetry breaking. We do not find any such Mexican-hat signature in the second Landau level Coulomb interaction at 5/2.

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Michael R. Peterson, Kwon Park, S. Das Sarma. 2008-10-09. Spontaneous Particle-Hole Symmetry Breaking in the $ν=5/2$ Fractional Quantum Hall Effect. https://doi.org/10.1103/physrevlett.101.156803

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