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Running slab waveguide program with large dimensions

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I have a slab waveguide and want to investigate waveguiding through it. I run the model on the wave optics module, frequency domain method.
The slab is defined as a polymer material with dipoles emitting at a certain wavelength. The emitted light propagates through the polymer and outputs at one end. What I want to do is change the thickness of the polymer from nm to several um, and see the effect on the beam output. The length of the waveguide is set to 5 um.

Problem:
The program works with a 2 um polymer thickness, taking only 4 hours to compute. However, I find that when I increase the polymer thickness to 4 um, the program does not run properly. To explain, the mesh works fast as normal but the program computation ran up to 70 % which took 16 hours and just didn't proceed any further. I let it run for 7 hours and still it sat at 70% completed. I calculated that it should have finished with additional 7-8 hours but was the progress bar still showed about 70% completion.

The model is run on a computer that has 2 processes, 16 core and 64 Gb RAM. Is this not sufficient processing capacity to run such dimensions? I saw in the tutorials that size can only be increased largely in one dimension, is this why the program is not working properly? If that is the case, is it possible to run something with large dimensions (several um) in all directions of x, y and z?

0 Replies Last Post 6 feb 2014, 11:10 GMT-5
COMSOL Moderator

Hello DImali Vithanage

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