New Method in version 5.3: "Angular Spectrum of Plane Waves" Diffraction Limited Gaussian Beam

Hi all,

I am currently trying to generate a diffraction limited gaussian beam (full width half max of around 200nm)

This is impossible under the paraxial approximation that was used to define Gaussian beams in older versions of Comsol.

In 5.3, Comsol updated adding the "Angular Spectrum of Plane Waves" method. In principle, this is supposed to be able to simulate tight focused beams.

Using this method, I can create tighter beams than in the older version of Comsol. However, the size of the beam is still far too large (5-10x as large as expected).

I am still playing with the parameters to try to get it to work, but has anyone used Comsol to make a diffraction limited gaussian beam? Can it be done? I have read the Comsol Blog Post "The Nonparaxial Gaussian Beam Formula for Simulating Wave Optics", but are there any other examples posted about this method?

Any information or insight could help me or future Comsol users.

Thanks!