Problem with Joule Heat Expression

1

Hi everyone,
I would like to calculate the heat generation in a FinFET, but I may have expressed the Joule heat formula incorrectly. The Joule heat is defined as:

H=\frac{|\vec{J}_n|^2}{q \mu_n n} + \frac{|\vec{J}_p|^2}{q \mu_p p}

In this expression, the mobility is field-dependent, so both the mobility and current density are represented in Element model. In my code, Joule heat implemented as follows:

JouleHeat=
"ElementElectronCurrent*ElementElectronCurrent/(mu_vsat_e*ElectronCharge*edgeElectrons)+
 ElementHoleCurrent*ElementHoleCurrent/(mu_bulk_h*ElectronCharge*edgeHoles)

I substituted the Joule heat expression into the heat conduction equation:

equation(device=device, region=region, name="HeatconductionEquation", variable_name="Temperature",
            volume_node0_model="JouleHeat ",volume_node1_model="JouleHeat",edge_model="TemperatureEdgeFlux",
            time_node_model="", variable_update="positive")

However, after completing the simulation, I found that the total heat generation is incorrect. I suspect that there might be an issue with the expression for Joule heat. Is there an error in the Joule heat expression in my code? I’m not sure whether the"ElementElectronCurrent*ElementElectronCurrent" in my code correctly represents the |\vec{J}_n|^2

Thanks a lot!