How to simulate heating induced by optical pulse travelling in medium

As described in my question about heating by optical pulse; I firstly used the Frequeny domain study of Beam Envelope Method to simulate the electric field distribution in waveguide. And I used the numerical port to input the power. Then I add the electricmagnetic heating multiphysics. And I can get the temperature distribution with time. But I want to define the input power as a function of time, It showed error about t when computed. Then I guess maybe the numerical port in frequency domain study can't be expressed as a function of time.
So I try to use the electricmagnetic wave transient module(ewt) to simulate the optical pulse heating. Use the scattering boundary conditon, the input electric field can be defined as a pulse. And the electric field with time can be obtained. But when added the heat solid transfer module, then added the heat source as ewt.Qh, I can't get the optical pulse induced heat distribution. I don't know what's the problem. If it caused by the time step or relative tolerance setting of the Time Dependent study or others?