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arXiv · 2305.11174

Magnetic catalysis in weakly interacting hyperbolic Dirac materials

Bitan Roy
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Abstract

Due to the linearly vanishing density of states, emergent massless Dirac quasiparticles resulting from the free fermion motion in a family of two-dimensional half-filled bipartite hyperbolic lattices feature dynamic mass generation through quantum phase transitions only for sufficiently strong finite-range Coulomb repulsion. As such, strong nearest-neighbor Coulomb repulsion ($V$) favors the nucleation of a charge-density-wave (CDW) order with a staggered pattern of average fermionic density between two sublattices of bipartite hyperbolic lattices. Considering a collection of spinless fermions (for simplicity), here we show that application of strong external magnetic fields by virtue of producing a \emph{finite} density of states near the zero energy triggers the condensation of the CDW order even for \emph{infinitesimal} $V$. The proposed curved space magnetic catalysis mechanism is operative for uniform and inhomogeneous (bell-shaped) magnetic fields. We present scaling of the CDW order with the total flux enclosed by hyperbolic Dirac materials for a wide range of (especially subcritical) $V$.

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Bitan Roy. 2023-05-18. Magnetic catalysis in weakly interacting hyperbolic Dirac materials. https://doi.org/10.1103/physrevb.110.245117

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