Volume emission in front of white background

Hi everyone,

I am trying to use Blender for creating a schematic for a scientific publication. I have already modeled what I imagined the end result to look like but I am struggling with the laser. I tried using LuxRender but am unhappy with the rather inconsistent results and limitations. So I went back to Cycles and settled for a less realistic laser: an emitting volume with some volume scattering to create speckles. I created this with a bezier curve so I can make it bounce around any way I want (also the taper function works nice for a Gaussian beam focus). My problem is that I would like to use a white background but it kills my volume lights completely.

Since I’m already asking… Any suggestions for the laser in general? Real lasers also have a Gaussian beam profile, so it shouldn’t be as bright on the edges as in the center. Would it be possible to make the intensity fall off inside the Nanowire (structure I modeled)? It is getting absorbed by the Nanowire in reality.

Thanks for your help.


taperedwire_cooling.blend (763 KB)

Update: Volume Absorption makes it appear in front of the white background. But it’s still not the prettiest laser imaginable. Suggestions anyone?