▎ 摘　　要

NOVELTY - The device (100) has a gate structure (102). A gate structure (104) is transparent or semi-transparent. A bilayer graphene (106) is coupled to the gate structure (102) and gate structure (104). The bilayer graphene is located partially between the gate structure (102) and the gate structure (104). The gate structure having an insulating layer (114) is composed of aluminum oxide. The electrode (112) is made of platinum. USE - Graphene device e.g. dual gate graphene FET. ADVANTAGE - Emphasizes the intrinsic potential of bilayer graphene for nano-electronics, as the gate-tunable bandgap, an order of magnitude higher than the room temperature thermal energy is achieved. Enables nano-photonic device for infrared light generation, amplification and detection, as the graphene device contains unusually strong oscillator strength for the band gap transition with tunable bandgap reached the infrared range. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) method for investigating semiconductor properties; and (2) method for operating graphene device. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of the graphene device. Graphene device (100) Gate structures (102,104) Bilayer graphene (106) Electrode (112) Insulating layer (114)