1. © intec 2000 Introduction to Kallistos B. Luyssaert

2. © intec 2003http://www.photonics.intec.rug.ac.be What is Kallistos ? Although commercialised by another company, Kallistos is an extension of FimmWave Optimisation tool capable of automatically improving existing photonic devices Contains several robust optimisers (local and global) Takes advantage of eigenmode expansion equations

3. © intec 2003http://www.photonics.intec.rug.ac.be The Following assumes a basic knowledge of FimmWave and FimmProp is based on an example that is delivered with Kallistos project: learn_kallistos.prj source node: example_MMI

4. © intec 2003http://www.photonics.intec.rug.ac.be Defined structure = MMI-coupler (defined using shapes, 2D, no PML) D W L

5. © intec 2003http://www.photonics.intec.rug.ac.be Field plot (clearly not in an optimum)

6. © intec 2003http://www.photonics.intec.rug.ac.be Right click project and add Kallistos Optimiser

7. © intec 2003http://www.photonics.intec.rug.ac.be Click Optimiser Symbol and Optimiser Window appears, note the 8 different symbols

8. © intec 2003http://www.photonics.intec.rug.ac.be Symbol1: select a node Select the node of the project you want to be optimised, in this case example_mmi

9. © intec 2003http://www.photonics.intec.rug.ac.be Symbol2: show node Trivial

10. © intec 2003http://www.photonics.intec.rug.ac.be Symbol3: Settings, PART 1: Optimiser Settings Global : search through the entire parameter space

11. © intec 2003http://www.photonics.intec.rug.ac.be Symbol3: Settings, PART 2: Independent Variables Define the parameters you want to be changed and the boundaries of the parameter space

12. © intec 2003http://www.photonics.intec.rug.ac.be Symbol3: Settings, PART 3: Dependent Variables Cdev = current device = selected node To know the number of each shape = watch command-line window during constructing of the node TIP: = autocompletion

13. © intec 2003http://www.photonics.intec.rug.ac.be Symbol3: Settings, PART 4: Objective 4 predefined objective functions: total power forward power backward power mode power User Defined Objectives: see manual

14. © intec 2003http://www.photonics.intec.rug.ac.be Symbol5: Run, PART 1: Tree View Watch the evolution of the optimisation Blue is bad, Red is good Crude scanning: Parameter space is divided in 2, middle point is evaluated, then best part is again divided in 2, evaluated,...

15. © intec 2003http://www.photonics.intec.rug.ac.be Symbol5: Run, PART 2: Hypercube View Watch the evolution of the optimisation Blue is bad, Red is good View a cross section of the parameter space hypercube and the quality of the points projected onto it

16. © intec 2003http://www.photonics.intec.rug.ac.be Symbol5: Run, PART 3: Data View Watch the evolution of the optimisation Shows the details of every calculated point and also the very best point with the related parameter values

17. © intec 2003http://www.photonics.intec.rug.ac.be Symbol5: Run, Update Initial

18. © intec 2003http://www.photonics.intec.rug.ac.be Symbol5: Run, Local Optimiser Optimise locally around best point

19. © intec 2003http://www.photonics.intec.rug.ac.be Symbol5: Run, Local Optimiser, Line Path View Watch the evolution of the local optimisation Top: evolution of objective function Bottom: evolution of parameters

20. © intec 2003http://www.photonics.intec.rug.ac.be Symbol8: Display node

21. © intec 2003http://www.photonics.intec.rug.ac.be Symbol7: Open Previous run Use: Suppose that you also would like to locally optimise the second best point of the global run Symbol6: Delete Current Run Symbol4: Block Editor Use: Input in text format, rather intuitive

22. © intec 2003http://www.photonics.intec.rug.ac.be Enjoy Kallistos !