Nanowire optoelectric switching device and method

1. A room temperature nanowire switching device comprising:

a nanowire structure comprising an elongated member having a cross-sectional diameter ranging from about 1 nanometers but less than about 300 nanometers;

a first terminal coupled to a first portion of the nanowire structure;

a second terminal coupled to a second portion of the nanowire structure, the second portion of the nanowire structure being disposed spatially from the first portion of the nanowire structure; and

an active surface structure comprising a first chemical species coupled to the nanowire structure, the active surface structure extending from the first portion to second portion along the elongated member;

whereupon the nanowire structure has a first conductivity value as measured between the first terminal and the second terminal while the active surface is subjected to a first intensity of electro-magnetic radiation illumination, the nanowire structure having a second conductivity value as measured between the first terminal and the second while the active surface is subjected to a second intensity of electro-magnetic radiation illumination;

wherein the electro-magnetic radiation illumination releases a portion of the first chemical species from the active surface structure;

wherein the first chemical species can be selected from O 2 , NO 2 , H 2 O, NO, and SO 2 ; and

wherein the device is operable at room temperature.

2. The device of claim 1 wherein the device is at least one of a switch, a sensor, a chemical sensor, photo-detector, an opto-electronic device, MEMS, and MEOMS.

3. The device of claim 1 wherein the device is a humidity sensor or an oxygen sensor.

4. The device of claim 1 wherein the nanowire structure is characterized by a shape of a nanowire.

5. The device of claim 1 wherein the active surface is about 10% to 90% of a total surface area of the nanowire structure.

6. The device of claim 1 wherein the cross-sectional diameter ranges from about 1 nm to 500 nm.

7. The device of claim 1 wherein the nanowire structure has an aspect ratio (length to diameter) of 10 to 1000.

8. The device of claim 1 wherein the nanowire is made of a material that substantially single crystal.

9. The device of claim 1 wherein the nanowire is made of a material that is polycrystalline.

10. The device of claim 1 wherein the nanowire structure is made of a material that is a semiconductor.

11. The device of claim 10 wherein the semiconductor material is ZnO, SiGe, Si, Ge, SnO 2 , GaN, PbSe, PbS, or Bi 2 Te 3 .

12. The device of claim 1 wherein nanowire structure comprises at least a first material and a second material that are spatially separated from each other.

13. The device of claim 1 wherein the nanowire structure is made of a homogeneous material.

14. The device of claim 1 wherein the nanowire is heterogeneous in texture.

15. The device of claim 1 wherein the second intensity level of the illumination being proportional to the second conductivity value.

16. The device of claim 1 wherein the device is substantially free from high temperature thermal elements.

17. The device of claim 1 wherein the device is operable at 0 to 100 Degrees Celsius.

18. A method for switching an opto-electronic device, the method comprising:

providing a nanowire structure having a surface region, the surface region having a first chemical species attached to the surface region of the nanowire structure, the nanowire structure having the first chemical species providing a first electrical state of the nanowire structure; and

illuminating energy onto the surface area of the nanowire structure to change the nanowire structure having the first chemical species from the first electrical state to a second electrical state whereupon the second electrical state allows a conduction characteristic of the nanowire to change from the first electrical state to the second electrical state;

wherein the illuminating releases a portion of the first chemical species from the surface area of the nanowire structure; and

wherein the first chemical species can be selected from O 2 , NO 2 , H 2 O, NO, and SO 2 .

19. The method of claim 18 wherein the illuminating converts the first chemical species into the second chemical species.

20. The method of claim 18 wherein the energy is electro-magnetic radiation.

21. The method of claim 18 wherein the nanowire structure is made of a semiconductor material.

22. The method of claim 21 wherein the semiconductor material is selected from ZnO, SiGe, Si, Ge, SnO 2 , TiO 2 , and GaN.

23. The method of claim 18 wherein the nanowire structure is single crystalline or polycrystalline.

24. A nanowire opto-electronic switching device comprising:

a nanowire structure comprising an elongated member having a cross-sectional diameter ranging from about 1 nanometers but less than about 300 nanometers;

a first terminal coupled to a first portion of the nanowire structure;

a second terminal coupled to a second portion of the nanowire structure, the second portion of the nanowire structure being disposed spatially from the first portion of the nanowire structure; and

an active surface structure comprising a first chemical species coupled to the nanowire structure, the active surface structure extending from the first portion to the second portion along the elongated member;

whereupon the nanowire structure has a first resistance value as measured between the first terminal and the second terminal while the active surface is subjected to a first level of electro-magnetic radiation, the nanowire structure having a second resistance value as measured between the first terminal and the second terminal while the active surface is subjected to a second level of electro-magnetic radiation;

wherein the release of a portion of the first chemical species from the active surface structure varies with the intensity of electro-magnetic radiation from the first level of electro-magnetic radiation and the second level of electro-magnetic radiation;

wherein the first chemical species can be selected from O 2 , NO 2 , H 2 O, NO, and SO 2 ; and

wherein the device is operable at room temperature.