Construct and maintain high-fidelity compact and behavioral representations for both active and passive silicon photonic elements, covering waveguides, couplers, MZIs, micro-rings, multiplexers, phase control elements, thermal tuners, modulators, detectors, and integrated III-V/SOA components. Implement integrated sub-circuit models for Passage interconnect blocks, including modulated ring arrays, filter banks, thermal controls, drive circuits, DWDM MUX/DEMUX structures, and receiver front-ends.