The self-consistent HARTREE self-energy due to electron-electron interaction
is given by 
3.6.1 Elecron-Electron Interaction
(see Section 3.9.1). The potential resulting from the HARTREE
self-energy is in fact the solution of the POISSON equation with the
charge density . The HARTREE self-energy is instantaneous.
M. Pourfath: Numerical Study of Quantum Transport in Carbon Nanotube-Based Transistors