Extended Data Fig. 5: Coupled-resonance-induced transparency and near-field coupling dependence.
From: Directive giant upconversion by supercritical bound states in the continuum
a, Spectral coincidence of the EIT transparency frequency at the avoided crossing with the FW quasi-BIC frequency for the angle mismatch <0.6°. b, Near-field coupling constant (real part) normalized to ω− = 2πc/λmode-1. c, associated quality-factor Qκ (as defined above) as a function of z (normalized to λmode-1 = 810 nm) along the z axis and parameterized for θ from 2.7° to 3.24°.