Fig. 4: Experimental observation of power splitting tuned by changing external magnetic fields.
From: Magnetically controllable multimode interference in topological photonic crystals
a, b The measured and theoretical (analytical) power splitting ratio of two CEMs as functions of magnetic field strength. The circles represent experimental data, lines depict the numerical results and the filled circles represent analytical results. The red (blue) color indicates the emitter is placed at channel S1(S2). Right panel: numerical electric field distributions at frequency of \(f=12.13\,{\rm{GHz}}\) along the left boundary of the A|Air|B heterostructure under distinct magnetic field strength: \(B=0.055{\rm{T}}\) (c), \(B=0.097{\rm{T}}\) (d) and \(B=0.175{\rm{T}}\) (e), respectively. Left panel: the measured electric field distributions, which are consistent with the associated numerical results
