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A thermally powered source of IR or THz radiation combines low dimension nano-scale oscillators such as nano-wires and nano-tubes with micro-scale photonic crystal resonant defect cavities for efficient generation, coupling and transmission of electromagnetic radiation. The oscillators have M=0, 1 o

A thermally powered source of IR or THz radiation combines low dimension nano-scale oscillators such as nano-wires and nano-tubes with micro-scale photonic crystal resonant defect cavities for efficient generation, coupling and transmission of electromagnetic radiation. The oscillators have M=0, 1 or 2 resonant dimensions on a micro-scale (approximately 1 um to approximately 1 mm) to emit radiation having a local peak at a desired wavelength in the IR or THz regions. The oscillators have at least one non-resonant dimension on a nano-scale (less than approximately 100 nm) to suppress vibration modes in that dimension and channel more thermal energy into the local peak. The photonic crystal defect cavities have N=1, 2 or 3 (NM) resonant dimensions on the microscale with lengths comparable to the length of the oscillator and the desired wavelength to exhibit a cavity resonant that overlaps the local peak to accept and transmit emitted radiation. The energy from multiple oscillator/defect cavities pairs can be collected and transmitted by an internal waveguide or external mirrors and lens to a specified location where it is output. To improve coupling efficiency, the oscillators and defect cavities preferably exhibit a physical symmetry so that they are substantially “mode matched”. The integration of nano-scale emitters with micro-scale photonic crystal defect cavities creates a new class of metamaterials that more efficient generate radiation.

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1. A source of radiation for a specified band of wavelengths, comprising: a photonic crystal that exhibits a band gap coincident with the specified band such that a wavelength within the band gap is substantially confined in at least one dimension within the photonic crystal;at least one void defect

1. A source of radiation for a specified band of wavelengths, comprising: a photonic crystal that exhibits a band gap coincident with the specified band such that a wavelength within the band gap is substantially confined in at least one dimension within the photonic crystal;at least one void defect cavity substantially within the photonic crystal that exhibits a cavity resonance within the band gap in N dimensions where N is an integer of value 1, 2 or 3;an oscillator substantially within the void defect cavity in the crystal, said oscillator resonating in M dimensions where M is an integer less than N of value 0, 1 or 2 to generate electromagnetic radiation having a spectrum that exhibits at least one local peak, one said local peak overlapping with said cavity resonance whereby the cavity accepts and transmits electromagnetic radiation in the local peak; andmeans for heating the oscillator to increase the electromagnetic radiation. 2. The source of radiation of claim 1, further comprising: a plurality of said oscillators substantially within a respective plurality of said void defect cavities substantially within the photonic crystal, andmeans for collecting electromagnetic radiation from the plurality of void defect cavities to a specified location. 3. The source of radiation of claim 2, wherein the total surface area of the plurality of void defect cavities is greater than the surface area of the photonic crystal. 4. The source of radiation of claim 2, wherein the means comprises a waveguide substantially within the photonic crystal that collects radiation from the plurality of void defect cavities and transmit the collected radiation to a specified location on the photonic crystal. 5. The source of radiation of claim 3, further comprising an antenna at the specified location to emit electromagnetic radiation in the specified band. 6. The source of radiation of claim 1, wherein the oscillator comprises an M=1 dimensional nanowire or nanotube. 7. The source of radiation of claim 6, wherein lengths of the oscillator and the void defect cavity in the resonant dimensions are approximately equal and comparable to wavelengths in the specified band and the void defect cavity has a diameter at least 1000 times greater than the diameter of the nanowire or nanotube. 8. The source of radiation of claim 1, wherein the lengths of the oscillator and the void defect cavity in the resonant dimensions where M=1 or 2 are approximately equal and comparable to wavelengths in the specified band. 9. The source of radiation of claim 1, wherein said oscillator generates electromagnetic radiation in a first mode and said void defect cavity accepts radiation in a second mode, said oscillator and cavity symmetrically configured so that said first and second modes substantially match. 10. The source of radiation of claim 9, wherein said void defect cavity comprises a cylindrical void that resonates in N=3 dimensions and said oscillator comprises a line source that resonates in M=1 dimension. 11. The source of radiation of claim 10, wherein the line source is positioned axially within the cylindrical void so that said first mode is substantially matched to a second axial mode of the cylindrical void. 12. The source of radiation of claim 10, wherein the line source is positioned radially within the cylindrical void so that said first mode is substantially matched to a second radial mode of the cylindrical void. 13. The source of radiation of claim 9, wherein said void defect cavity comprises a planar void that resonates in two dimensions and said oscillator comprises a line source that resonates in one dimension. 14. The source of radiation of claim 9, wherein said void defect cavity comprises a cuboid void that resonates in three dimensions and said oscillator comprises a thin sheet that resonates in two dimensions. 15. The source of radiation of claim 9, wherein said void defect cavity comprises an N=1 dimensional cavity and said oscillator comprises an M=0 oscillator. 16. The source of radiation of claim 1, further comprising a plurality of said oscillators substantially within the void defect cavity and spaced so that the generated electromagnetic radiation is reinforced. 17. The source of radiation of claim 1, wherein the specified band lies in the THz region of approximately 0.3-10 THz, said defect cavity and said oscillator having approximately the same length in a range of approximately 1 mm to approximately 30 microns, said oscillator having a dimension of no greater than approximately 100 nm in a non-resonant dimension and said cavity having a resonant dimension of approximately 1 mm to approximately 30 microns in that same dimension. 18. The source of radiation of claim 1, wherein the specified band lies in the IR region of approximately 10-300 THz, said defect cavity and said oscillator having approximately the same length in a range of approximately 30 microns to approximately 1 micron, said oscillator having a dimension of no greater than approximately 100 nm in a non-resonant dimension and said cavity having a resonant dimension of approximately 30 microns to approximately one micron in that same dimension. 19. A method of generating radiation in a specified band of wavelengths, comprising: providing a plurality of oscillators that resonate in M dimensions where M is an integer of value 0, 1 or 2 to generate electromagnetic radiation having a spectrum that exhibits at least one local peak;heating the oscillators to increase the electromagnetic radiation;coupling the one said local peak of the oscillators' spectrums to respective void defect cavities substantially within a photonic crystal that exhibit a cavity resonance that overlap the local peak within a band gap coincident with the specified band in N dimensions where N is an integer greater than M of value 1, 2 or 3;collecting the electromagnetic radiation in the local peak from the plurality of void defect cavities at a specified location; and transmitting the collected electromagnetic radiation. 20. The method of claim 19, where said oscillators generate electromagnetic radiation in a first mode and said void defect cavities accept radiation in a second mode, said oscillator and cavity symmetrically configured so that said first and second modes substantially match. 21. The method of claim 19, wherein the specified band lies in the THz region of approximately 0.3-10 THz, said paired defect cavity and said oscillator having approximately the same length in a range of approximately 1 mm to approximately 30 um, said oscillator having a dimension of no greater than approximately 100 nm in a non-resonant dimension and said cavity having a resonant dimension of approximately 1 mm to approximately 30 um in that same dimension. 22. The method of claim 19, wherein the specified band lies in the IR region of approximately 10-300 THz, said paired defect cavity and said oscillator having approximately the same length in a range of approximately 30 microns to approximately 1 micron, said oscillator having a dimension of no greater than approximately 100 nm in a non-resonant dimension and said cavity having a resonant dimension of approximately 30 microns to approximately 1 micron in that same dimension. 23. A source of radiation for a specified band of wavelengths in the THz (0.3-10 THz) or IR (10-300 THz) regions, comprising: a photonic crystal that exhibits a band gap coincident with the specified band such that a wavelength within the band gap is substantially confined in at least one dimension within the photonic crystal;a plurality of void defect cavities substantially within the photonic crystal, each said defect cavity exhibiting a cavity resonance within the band gap in N dimensions where N is an integer of value 2 or 3 and accepting electromagnetic radiation in a first mode, each of said N dimensions having a physical extent comparable to a center wavelength of the specified band of between approximately 1 micron and approximately 1 mm;a plurality of nano-scale oscillators substantially within a respective one of the void defect cavities in the crystal, each said oscillator generating electromagnetic radiation in a second mode that is substantially matched to said first mode, said radiation having a spectrum that exhibits at least one local peak, each said oscillator resonating in M dimensions where M is an integer less than N of value 1 or 2, each of said M dimensions having a physical extent comparable to a center wavelength of the specified band between approximately 1 micron and approximately 1 mm and said at least one non-resonant dimensions having a physical extent less than approximately 100 nm, one said local peak overlapping with said cavity resonance whereby the cavity accepts and transmits the electromagnetic radiation in the local peak;means for heating the oscillator to increase the electromagnetic radiation; andmeans for collecting electromagnetic radiation from the plurality of void defect cavities at a specified location. 24. The source of radiation of claim 23, wherein said oscillator generates electromagnetic radiation in a first mode and said void defect cavity accepts radiation in a second mode, said oscillator and cavity symmetrically configured so that said first and second modes substantially match.