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arXiv · 2005.01990

Quantum criticality of magnetic catalysis in two-dimensional correlated Dirac fermions

Yasuhiro Tada
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Abstract

We study quantum criticality of the magnetic field induced charge density wave (CDW) order in correlated spinless Dirac fermions on the $\pi$-flux square lattice at zero temperature as a prototypical example of the magnetic catalysis, by using the infinite density matrix renormalization group. It is found that the CDW order parameter $M(B)$ exhibits an anomalous magnetic field $(B)$ scaling behavior characteristic of the $(2+1)$-dimensional chiral Ising universality class near the quantum critical point, which leads to a strong enhancement of $M(B)$ compared with a mean field result. We also establish a global phase diagram in the interaction-magnetic field plane for the fermionic quantum criticality.

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Yasuhiro Tada. 2020-05-05. Quantum criticality of magnetic catalysis in two-dimensional correlated Dirac fermions. https://doi.org/10.1103/physrevresearch.2.033363

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