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arXiv · 1806.00508

Dynamical symmetry in a minimal dimeric complex

E. Sadurní·Y. Hernández-Espinosa
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Abstract

The emergence of non-configurational symmetry is studied in a minimal example. The system under scrutiny consists of a dimeric hexagonal complex with configurational $C_3$ symmetry, formulated as a tight-binding model. An accidental three-fold degeneracy point in parameter space is found; it is shown that an internal $U(3)$ symmetry group operates on Hilbert space, but not on configuration space. The corresponding discrete Wigner functions for the irreducible representations of $C_6 \cong C_3 \times Z_2$ are utilized to show that a $6\times 6$ phase space is sufficient to exhibit an invariant subset. The dynamical symmetry is thus identified with a discrete semi-plane. Some implications on other known hidden symmetries of continuous systems are qualitatively discussed.

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E. Sadurní, Y. Hernández-Espinosa. 2018-06-01. Dynamical symmetry in a minimal dimeric complex. https://doi.org/10.1088/1751-8121/ab25b6

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