Line Plot from Scientific Research

Upper panels: this work (c). The red (blue) circles represent the sublattices with on-site energy m (- m) and the black lines indicate the nearest-neighbor couplings with strength t. The larger (smaller) black arrows in (c) denote the NNN couplings t2 + delta (t2 - delta). Lower panels: Schematics of the Dirac cone dispersion of the non-Hermitian model in this work (c). In this work, a complex conjugate pair of Dirac cones at the K and K' valleys are related to one another by the TRS, with colors denoting the imaginary parts of the eigenvalues. In the long time limit, only states at the K valley will survive due to the sharp contrast in lifetime between the two valleys, leading to an effective single Dirac cone behavior over a large energy range as indicated by the orange dashed lines.

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