1. A. Freise 22.07.2006 FINESSE + FINESSE + future plans and work in progress Andreas Freise 22nd July 2006

2. A. Freise 22.07.2006 FINESSE http://www.rzg.mpg.de/~adf/

3. A. Freise 22.07.2006 Which Version to Use? 0.99.3 -> current (22.07.2006) fixed bugs: o several memory/pointer errors but none showed any difference when running test examples

4. A. Freise 22.07.2006 Which Version to Use? 0.99.2 -> 0.99.3 (25.02.2006) fixed bugs: o 'cav' tracing did not find its way through a BS when approaching it from node 4.

5. A. Freise 22.07.2006 Which Version to Use? 0.99.1 -> 0.99.2 (26.10.2005) fixed bugs: o a 'retrace' on an unstable cavity or 'retrace' with no 'cav' nor 'gauss' command caused a "bug found" message. o the 'func' command could not parse function strings with multiple occurences of the same variable name. o the phase delay on propagation through a 'space' component had the wrong sign. This basically flipped the frequency dependence, e.g. upper sidebands were behaving like lower sidebands and vice-versa. This must have been wrong since the beginning of Finesse. Should affect almost all results but mostly by only switching frequency signs.

6. A. Freise 22.07.2006 Which Version to Use? 0.99 -> 0.99.1 (26.08.2005) fixed bugs: o inconsistency in definition of demodulation phase o a pointer error in the function call for the evaluation of 'func' commands caused some arbitrary results when more than one argument was used o a memory allocation error occurred when 'bp' detectors were used together with other detector types o demodulating at a signal frequency introduced a factor of 0.5 for all demodulations except for the standard transfer function with a pd2.

7. A. Freise 22.07.2006 Ways to Improve FINESSE  collect simualtion examples for validation/verification  develop and collect tools for automation and data post-processing  improve performance, flexibility of the FINESSE binary  add new components, mainly for non-classic interferometry  gratings  quantum noise  polarisation

8. A. Freise 22.07.2006 The FINESSE Test Suite  Nightly run of the latest version against several hundret example files.  What is missing, is a set of files which have been checked by an independent user against calculation and/or experimental data Testing: -------- Thu Jul 20 10:46:08 BST 2006 Entering physics... OK: darkf-comp.kat OK: grating1.kat Entering random... OK: 00all_gouy.kat OK: 00first.kat OK: 01cavity-mode.kat OK: 01resoances.kat OK: 01tilt.kat OK: 02fringes-pm.kat OK: 02fringes-untuned.kat OK: 02fringes.kat OK: 03mode-separation.kat OK: 04modulation-b.kat OK: 04modulation-c.kat OK: 04modulation.kat OK: 05IB.kat OK: 06matching.kat OK: 07CCD.kat OK: 08telescope.kat ….

9. A. Freise 22.07.2006 Data Post-Processing  Automate certain simulation tasks  Perform data mining, data preparation  Example 1: complex control matrices  Example 2: „tolerancing“

10. A. Freise 22.07.2006 Getting More out of FINESSE  Change FINESSE input/output so that the binary can be called as a function from other programs, e.g. Matlab/Octave  started by Martin Hewitson, copying the idea of his data server: Threaded server ‘katd’ Client3 Client2 Client1 Server ‘katd’ started with input file, without ‘xaxis’ Clients send commands like: component parameter value and receive one result (data point) per command TCP/IP

11. A. Freise 22.07.2006 Going Parallel  Beowulf Cluster:  Python script reads input file, „understand“ the dimension of the parameter space (I.e. xaxis, x2axis) and creates N new input files, submits them via Condor to the cluster and then merges the N output files (student project, first examples work!)  MPI Cluster (true parallel computing)  FINESSE spends 90% of its time in the Sparse routines „solving“ the set of linear equations. This package can be replaced by a modern one which can be optimised for MPI compilers. Then each data point is computed on aparallel computer. (another student project?)

12. A. Freise 22.07.2006 Quantum Noise in FINESSE  Quantum noise can be computed after the standard calculation has been completed.  An almost identical procedure is used for building the the quantum noise matrix

13. A. Freise 22.07.2006 Quantum Noise in FINESSE  Quantum noise can be computed after the standard calculation has been completed.  An almost identical procedure is used for building the the quantum noise matrix

14. A. Freise 22.07.2006 Quantum Noise in FINESSE  Prepared a second interferometer matrix to compute quantum noise couplings  use field amplitudes and mirror masses as input parameters  treat every port as a potential input of vacuum  vacuum can be squeezed  Missing:  coupling equations (exist)  some understanding of how to work with multiple fields  testing!

15. A. Freise 22.07.2006 Conclusion  FINESSE is alive and changing  A communty effort would make it better (especially with respect to add-on tools)  Simulation work for commissioning might be the best way to document and preserve knowledge. Don‘t build an interferometer that way next time!

16. A. Freise 22.07.2006 End