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تسجيل مستخدم جديدCounter-propagating Fractional Hall states in mirror-symmetric Dirac semi-metals
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Yafis Barlas
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The Landau bands of mirror symmetric 2D Dirac semi-metals (for example odd-layers of ABA-graphene) can be identified by their parity with respect to mirror symmetry. This symmetry facilitates a new class of counter-propagating Hall states at opposite but equal electron and hole filling factors $| u_{pm}|=1/m$ ({it m} odd). Here, we propose a Laughlin-like correlated liquid wavefunction, at the charge neutrality point, that exhibits fractionally charged quasi-particle/hole pair excitation of opposite parity. Using a bosonized one-dimensional edge state theory, we show that the longitudinal conductance of this state, $sigma_{xx} = 2e^2/(m h)$, is robust to short-ranged inter-mode interactions.
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