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arXiv · 2107.08899

Critical properties of quantum three- and four-state Potts models with boundaries polarized along the transverse field

Natalia Chepiga
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Abstract

By computing the low-lying energy excitation spectra with the density matrix renormalization group algorithm we show that boundaries polarized in the direction of the transverse field lead to scale-invariant conformal towers of states at the critical point of the quantum four-state Potts model - a special symmetric case of the Ashkin-Teller model. Furthermore, by direct comparison of the excitation spectra we phenomenologically establish the duality between the transverse-polarized and three-state-mixed boundary conditions at the four-state Potts critical point. Finally, for completeness, we verify that in the quantum three-state Potts model the "new" boundary conditions dual to the mixed ones can be realized by polarizing edge spins along the transverse field.

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Natalia Chepiga. 2021-07-19. Critical properties of quantum three- and four-state Potts models with boundaries polarized along the transverse field. https://doi.org/10.21468/scipostphyscore.5.2.031

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