Gated organic light-emitting diodes or vertical light emitting transistors are disclosed based on the modulation of charge carrier injection from electrodes into light-emitting materials by applying external gate potential. This gate modulation were achieved in two disclosed methods: 1) a porous electrode allowing mobile ions to stabilize electrochemically doped semiconducting materials that can form ohmic contact with electrodes; 2) an electrode with gate- tunable work function such as Al:LiF composite electrodes.
