Optoelectronic devices utilizing materials having enhanced electronic transitions
View Patent ↗An optoelectronic device that includes a material having enhanced electronic transitions. The electronic transitions are enhanced by mixing electronic states at an interface. The interface may be formed by a nano-well, a nano-dot, or a nano-wire.
1. An optoelectronic device, the device comprising: (a) a first conductor; (b) a second, solid conductor; and (c) a material disposed between the first conductor and the solid conductor such that at least a portion of the material is in electrical contact forming a continuous conduction path with the first conductor and the second, solid conductor, wherein the material has a Fermi energy level, a plurality of carrier pockets, and an interface, wherein significant mixing of electronic states is achieved at the interface resulting in mixed electronic states, wherein the mixed electronic states comprise an initial state that is below or within kT of the Fermi energy level and a second state that is greater than or within kT of the Fermi energy level, wherein k is the Boltzmann constant and T is temperature in degrees Kelvin.
2. The optoelectronic device according to claim 1 , wherein the material comprises a plurality of nano-wires such that at least a portion of the plurality of nanowires is in electrical contact with the first conductor and the solid conductor.
3. The optoelectronic device according to claim 2 , wherein each of the plurality of nano-wires has a diameter of up to about 200 nm.
4. The optoelectronic device according to claim 3 , wherein each of the plurality of nano-wires has a diameter in a range from about 50 nm to about 200 nm.
5. The optoelectronic device according to claim 2 , wherein each of the plurality of nano-wires has a crystallographic orientation <hkl>, wherein h+k+l=0, −h+k+l=0, h−k+l=0, or h+k−l=0, and wherein h≠0, k≠0, and l≠0.
6. The optoelectronic device according to claim 5 , wherein the plurality of nano-wires comprises silicon nano-wires, and wherein each of the silicon nano-wires has a direction in a crystallographic orientation selected from the group consisting of <1-21>, <211>, <121>, and <112> orientations.
7. The optoelectronic device according to claim 2 , wherein the plurality of nano-wires comprises bismuth nano-wires, and wherein each of the bismuth nanowires has a direction in a crystallographic orientation selected from the group consisting of <101> and <012> orientations.
8. The optoelectronic device according to claim 2 , further comprising an insulating material disposed between the plurality of nano-wires.
9. The optoelectronic device according to claim 8 , wherein the insulating material comprises alumina.
10. The optoelectronic device according to claim 1 , wherein the material comprises a substance selected from the group consisting of silicon, bismuth, zinc, zinc sulfide, indium phosphide, indium arsenide, and combinations thereof.
11. The optoelectronic device according to claim 1 , wherein the material comprises at least one nano-dot.
12. The optoelectronic device according to claim 1 , wherein the material comprises at least one nano-well.
13. The optoelectronic device according to claim 1 , wherein the optoelectronic device is one of a light emitting diode, an infrared detector, an emitter, a solar cell, and a photovoltaic cell.
14. The optoelectronic device according to claim 13 , wherein the emitter is one of a near infrared emitter, a blue emitter, a red emitter, and a near UV emitter.
15. The optoelectronic device of claim 13 , wherein the device is an intermediate band solar cell.
16. The optoelectronic device of claim 15 , wherein the material comprises silicon, and the Γ point valence band to L-point conduction band electronic transition is enhanced and lies between about 1.65 and 2.29 eV.
17. The optoelectronic device of claim 1 , wherein the mixing of electronic states at the interface is such that the spatial overlap of two states is at least about 7 percent.
18. A method of manufacturing an optoelectronic device, wherein the method comprises the steps of (a) selecting a crystalline orientation for nano-wires which results in significant mixing of electronic states being achieved at a interface of the nano-wires, resulting in mixed electronic states, (b) fabricating a nanowire array having the selected crystalline orientation, (c) providing the nanowire array with a first conductor on one side of the nano-wire array and a solid conductor on a second side of the array, forming a continuous conduction path between the nanowire array and the first conductor and solid conductor respectively.
19. The method of claim 18 , comprising the step of disposing an insulating material between the nanowires.