Nanowire devices and systems, light-emitting nanowires, and methods of precisely positioning nanoparticles

1. A radiation-emitting device comprising:

a first electrode:

a second electrode;

at least one nanowire extending between the first electrode and the second electrode, the nanowire being structurally and electrically coupled to the first electrode and the second electrode, the nanowire comprising a double-heterostructure semiconductor device configured to emit electromagnetic radiation when a voltage is applied across the nanowire between the first electrode and the second electrode a first longitudinal segment comprising an n-type semiconductor material;

a second active longitudinal segment comprising a first p-type semiconductor material, the second active longitudinal segment being structurally and electrically coupled to an end of the first longitudinal segment; and

a third longitudinal segment comprising a second p-type semiconductor material, the third longitudinal segment being structurally and electrically coupled to an end of the second active longitudinal segment opposite the first longitudinal segment; and

wherein the first p-type semiconductor material differs from both the n-type semiconductor material and the second p-type semiconductor material.

2. The radiation-emitting device of claim 1 , wherein the first p-type semiconductor material exhibits a bandgap differing from both bandgap exhibited by the n-type semiconductor material and a bandgap exhibited by the second p-type semiconductor material.

3. The radiation-emitting device of claim 2 , wherein the bandgap exhibited by the n-type semiconductor material is equal to the bandgap exhibited by the second p-type semiconductor material.

4. The radiation-emitting device of claim 1 , wherein the n-type semiconductor material comprises a silicon-based material or a germanium-based material, the first p-type semiconductor material comprises a silicon-based material or a germanium-based material, and the second p-type semiconductor material comprises a silicon-based material or a germanium-based material.

5. The radiation-emitting device of claim 1 , wherein the first electrode comprises an n-type semiconductor material, the first longitudinal segment of the nanowire being structurally and electrically coupled to the first electrode, and wherein the second electrode comprises a p-type semiconductor material, the third longitudinal segment of the nanowire being structurally and electrically coupled to the second electrode.

6. The radiation-emitting device of claim 1 , wherein the nanowire is configured to emit electromagnetic radiation having a wavelength within a range extending from about 400 nanometers to about 800 nanometers when a voltage is applied across the nanowire between the first electrode and the second electrode.

7. The radiation-emitting device of claim 1 , wherein the nanowire comprises erbium or boron ions.

8. A radiation-emitting device comprising:

a first electrode:

a second electrode:

at least one nanowire extending between the first electrode and the second electrode, the nanowire being structurally and electrically coupled to the first electrode and the second electrode, the nanowire comprising a double-heterostructure semiconductor device configured to emit electromagnetic radiation when a voltage is applied across the nanowire between the first electrode and the second electrode; and

a resonant cavity, the nanowire being disposed within the resonant cavity.

9. The device of claim 8 , wherein the resonant cavity is configured to resonate at least one wavelength of electromagnetic radiation within a range extending from about 300 nanometers to about 2,000 nanometers; and

the nanowire is disposed within the resonant cavity, the nanowire comprising an active longitudinal segment comprising an active material, the active longitudinal segment being selectively disposed at a predetermined location within the resonant cavity, the active material being capable of emitting electromagnetic radiation at the at least one wavelength.

10. The device of claim 9 , wherein the active longitudinal segment of the nanowire is selectively disposed at a predetermined location within the resonant cavity to maximize the energy within the resonant cavity when the nanowire is emitting electromagnetic radiation at the at least one wavelength.

11. The device of claim 9 , wherein the resonant cavity comprises:

a first substantially planar member having a reflectivity greater than zero with respect to the at least one wavelength of electromagnetic radiation emitted by the active longitudinal segment of the nanowire, and

a second substantially planar member having a reflectivity greater than zero with respect to the at least one wavelength of electromagnetic radiation emitted by the active longitudinal segment of the nanowire.

12. The device of claim 11 , wherein at least one of the first substantially planar member and the second substantially planar member has a reflectivity less than one hundred percent with respect to the at least one wavelength of electromagnetic radiation emitted by the active longitudinal segment of the nanowire.

13. The device of claim 11 , wherein at least one of the first substantially planar member and the second substantially planar member comprises a Bragg mirror.

14. The device of claim 11 , wherein at least one of the first substantially planar member and the second substantially planar member comprises a thin layer of reflective material.

15. The device of claim 9 , wherein the resonant cavity is disposed within a photonic crystal.

16. The device of claim 9 , wherein the active material comprises a material doped with erbium ions.