Difference between laser heating and microwave heating

Hi, I got a question about the heat transfer module in comsol. The version I used is 5.3a.

There is a electromagnetic heating branch under the heat transfer module, which contains two sub-branchs: laser heating and microwave heating. According tot the introduction, both sub-branches combines the electromagntic wave frequency domain solver and the heat transfer in solid solver. The difference is that there is an addition beam evenlop solver for the laser heating, whereas it is absent in the microwave heating.

I wonder what could be the differences between these two methods? What is the use of the beam evenlop interface in the laser heating, to set guassian beam profile? If it is so, can we also do it manually in the micowave heating, i.e. with the port function?

Please help me to clarify this point.

Thank you in advance.