Tunable graphene light-emitting device

A device comprising:

• a substrate;
• a tunnel barrier disposed on an active region defined on the substrate;
• at least one monolayer of graphene disposed on the tunnel barrier;
• a dielectric material disposed on the monolayer of graphene,
• an electrode disposed over a portion of the dielectric material;
• a first electrical contact disposed over a portion of the monolayer of graphene;
• a second electrical contact disposed over a portion of the dielectric material;
• a third electrical contact disposed over a portion of the substrate;
• a first voltage source connected between the first electrical contact and the second electrical contact, the first voltage source configured to apply a first voltage to adjust a Fermi level within the monolayer of graphene to a Fermi level position within a valence band of the monolayer of graphene based upon a predetermined emission wavelength;
• and
• a second voltage source connected between the first electrical contact and the third electrical contact, the second voltage source configured to apply a second voltage to inject a current into a conduction band of the monolayer of graphene to cause the monolayer of graphene to emit photons at the predetermined emission wavelength.

A device comprising:

• a substrate;
• a tunnel barrier disposed on an active region defined on the substrate;
• at least one monolayer of graphene disposed on the tunnel barrier;
• a dielectric material disposed on the monolayer of graphene,
• an optically-transparent electrode disposed over a portion of the dielectric material;
• a first electrical contact disposed over a portion of the monolayer of graphene lying outside of the active region defined on the substrate;
• a second electrical contact disposed over a portion of the dielectric material and electrically connected to the optically-transparent electrode in the active region defined on the substrate;
• a third electrical contact disposed over a portion of the substrate;
• a first voltage source connected between the first electrical contact and the second electrical contact, the first voltage source configured to apply a first voltage to adjust a Fermi level within the monolayer of graphene to a Fermi level position within a valence band of the monolayer of graphene based upon a predetermined emission wavelength;
• and
• a second voltage source connected between the first electrical contact and the third electrical contact, the second voltage source configured to apply a second voltage to inject a current into a conduction band of the monolayer of graphene to cause the monolayer of graphene to emit photons at the predetermined emission wavelength.