How to combine PML and Port together By Comsol 4.3

Hi,

I am simulating the surface plasmon resonance. I use pot to set the incident TM plane wave. It looks that there is still some reflection from my port boundary. I want to add a PML to absorb the light. It seems that Comsol 4.3 doesn't support it. Is there any way I can solve this problem? Any other better solution for this?

Thank you very much for your help.

Best,
Yan