In a specially designed three barrier double well tunneling structure, elect ron injecting from the emitter in combination with escaping through a resonant tunneling structure were used to adjust and control the filling of electrons in different subbands. It was observed that the occupation in the first excited electron state can result in a suppression to quantum confinement Stark effect. Mo reover, at very low bias, a series of intrigue photoluminescence peaks appeared as a small quantity of excess electron was filled in the ground state of the qua ntum well, that cannot be explained by the theory of band to band transition in the framework of single electron picture.