As far as I understand, for NEGF model, the 2d electron density is first computed though integral of (Fermi function)*spectral density over energy, then the 3d electron density is obtained by multiply this 2d values by the wavefuntions located in all the nodes in the whole domain. I am wondering in the last output figure, how we obtain the 2d electron density along the channel, is it though dealing with the 3d electron density profile or it is just based on the 2d values obtained from the integral?

Thanks.