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Regarding integral forms

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I would like to do some calculations using the results from surface integration.

Can I introduce the following function(or equation) to COMSOL?

For instance:
gamma = k0*(integral integral [n2(x,y)*|emw|^4] dx dy / (integral integral |emw|^2 dx dy)^2

k0 : wave number
n2(x,y) : non-linear refractive index
|emw| : magnitude of electric field

When there are the square form of the emw, other parameter in the integral result, it is difficult in calculating those expression.

Thanks,
Yong-soo Kim.

1 Reply Last Post 14.10.2011, 02:08 GMT-4

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Posted: 1 decade ago 14.10.2011, 02:08 GMT-4
I found a clue that would lead to the solution of the problem.

In COMSOL 4.0a or 4.2, Results-Derived Values-Integration-Surface Integration-Selection(Some Domain)-Expression(2.48e-20[m^2/W]*abs(emw.normE)^4)-Evaluate-New Table.

==========================================================================================
gamma = k0*(integral integral [n2(x,y)*|emw|^4] dx dy / (integral integral |emw|^2 dx dy)^2

k0 : wave number
n2(x,y) : non-linear refractive index
|emw| : magnitude of electric field
==========================================================================================

I have obtained some value of the results, now I'm verifying those values.

But there was one problem. 'x', 'y' are the parameter as width, height of the core of the optical waveguide,respectively. I adjust the 'x', 'y' from '4um', '2um' to '16um', '4.5um', and I plot the results as contour plot.(In other words, 'x', 'y' are parameterized as width, height of the core, and then plotted the contour of the integral results)
I found a clue that would lead to the solution of the problem. In COMSOL 4.0a or 4.2, Results-Derived Values-Integration-Surface Integration-Selection(Some Domain)-Expression(2.48e-20[m^2/W]*abs(emw.normE)^4)-Evaluate-New Table. ========================================================================================== gamma = k0*(integral integral [n2(x,y)*|emw|^4] dx dy / (integral integral |emw|^2 dx dy)^2 k0 : wave number n2(x,y) : non-linear refractive index |emw| : magnitude of electric field ========================================================================================== I have obtained some value of the results, now I'm verifying those values. But there was one problem. 'x', 'y' are the parameter as width, height of the core of the optical waveguide,respectively. I adjust the 'x', 'y' from '4um', '2um' to '16um', '4.5um', and I plot the results as contour plot.(In other words, 'x', 'y' are parameterized as width, height of the core, and then plotted the contour of the integral results)

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