Fig. 4
From: Large-scale optical switches by thermo-optic waveguide lens
The crosstalk characterization on the neighboring ports adjacent to the target port a #14, b #18, c #1 and d #24. The solid lines indicate the crosstalk without activating the on-chip VOA, where the worst crosstalk is lower than -13.1 dB. The dashed lines are the measurement when the respective VOA is turned on, where the crosstalk level is suppressed below -30 dB regardless of polarization and for all wavelengths