OpenLane is an automated RTL to GDSII pipeline that includes OpenROAD, Yosys, Magic, Netgen, Fault, CVC SPEF-Extractor, CU-GR, Klayout, and a variety of scripts for design exploration and optimization.
Here's this Link to enter the on-line Xic help system.
@http://www.wrcad.com/cgi-bin/xichelp.cgi?h=xic.
3- Lumerical's tools enable the design of photonic components, circuits, and systems, Lumerical's DEVICE Suite of component-level simulation products use multiphysics-style simulation workflows to model optical, electrical and thermal effects at the physical level. Lumerical's SYSTEM Suite of system-level simulation products offer a rich set of analysis capabilities to design and optimize the performance of photonic integrated circuits. You can Importing and exporting GDSII files via using it.
Lumerical is part of the Ansys family.
3- GDoeSII – From Simulation to Fabrication. GDoeSII offers a complete platform for scalar diffraction simulations to lithography file generation.
@http://www.ee.iitm.ac.in/AppliedOptics/gdoesii/.
Also you may benefit from these pdf files about your topic, which i attached...