Broad wavelength range chemically tunable photonic materials
The present invention provides polymeric materials arranged as photonic crystals, or portions of photonic crystals, having properties which can be easily tuned over a large range of wavelengths upon exposure to an external stimulus. In some embodiments, the photonic crystals comprise at least one portion which can undergo a change in a physical, chemical, dielectric, or other property upon exposure to an altering stimulus, resulting in a change in a diffracted wavelength of electromagnetic radiation (e.g, light) by the photonic crystal. Embodiments of the invention may advantageously exhibit large stop band tunability and rapid response times. Photonic crystals of the invention may be useful in a wide variety of applications, such as colorimetric sensors, active components of simple display devices, electrically controlled tunable optically pumped laser, photonic switches, multiband filters, and the like.
1. A photonic material, comprising:
a polymeric article including a periodic structure of a plurality of periodically occurring separate domains able to interact with and affect electromagnetic radiation, with at least a first and a second domain each having an electromagnetic radiation-affecting dimension of at least 5 nm, and each having a dielectric constant such that the domains define a dielectric constant ratio of at least 1.001 for at least one range of continuous wavelengths lying within a range of from 10 nm to 10 microns,
wherein, in the presence of an altering stimulus, the electromagnetic radiation-affecting dimension of one of the domains changes relative to that of the other due to swelling and/or de-swelling of at least one of the domains, and a diffracted wavelength of electromagnetic radiation, having a diffracted wavelength greater than 700 nm, changes by at least 10 nm at a set point of observation relative to the photonic material.
2. The photonic material of claim 1 , wherein at least a portion of the polymeric article comprises a gel or polyelectrolyte.
3. The photonic material of claim 1 , wherein the polymeric article comprises a block copolymer.
4. The photonic material of claim 3 , wherein the block copolymer comprises at least one domain comprising a gel or polyelectrolyte.
5. The photonic material of claim 3 , wherein the block copolymer is polystyrene-quaternized-poly-(2-vinyl pyridine).
6. The photonic material of claim 1 , wherein the altering stimulus is a temperature change, a pH change, a fluid, electromagnetic radiation, an electric field, a magnetic field, a chemical agent, or pressure.
7. The photonic material of claim 1 , wherein the diffracted wavelength of electromagnetic radiation changes by at least 25 nm at the set point of observation relative to the photonic material.
8. The photonic material of claim 1 , wherein the diffracted wavelength of electromagnetic radiation changes by at least 50 nm at the set point of observation relative to the photonic material.
9. The photonic material of claim 1 , wherein the diffracted wavelength of electromagnetic radiation changes by at least 100 nm at the set point of observation relative to the photonic material.
10. The photonic material of claim 1 , wherein the diffracted wavelength of electromagnetic radiation changes by at least 150 nm at the set point of observation relative to the photonic material.
11. The photonic material of claim 1 , wherein the diffracted wavelength of electromagnetic radiation changes by at least 200 nm at the set point of observation relative to the photonic material.
12. The photonic material of claim 1 , wherein the diffracted wavelength of electromagnetic radiation changes by at least 250 nm at the set point of observation relative to the photonic material.
13. The photonic material of claim 1 , wherein the dielectric constant ratio is at least 1.01.
14. The photonic material of claim 1 , wherein the dielectric constant ratio is at least 1.1.
15. The photonic material of claim 1 , wherein the dielectric constant ratio is at least 1.25.
16. The photonic material of claim 1 , wherein the dielectric constant ratio is at least 1.5.
17. The photonic material of claim 1 , wherein the dielectric constant ratio is at least 1.75.
18. The photonic material of claim 1 , wherein the dielectric constant ratio is at least 2.0.