Electro-optic chromophore having an edot structure, and related methods and apparatuses
View Patent ↗In various embodiments, chromophores are described that include novel election acceptors, novel electron donors, and/or novel conjugated bridges that are useful in nonlinear optical applications. In some embodiments, the present invention provides chromophore architectures wherein a chromophore contains more than one electron acceptor in electronic communication with a single election donor, and/or more than one electron donor in electronic communication with a single electron acceptor. Also described is processes for providing materials comprising the novel chromophores and polymer matrices containing the novel chromophores. Electro-optic devices described herein contain one or more of the described electron acceptors, electron donors, conjugated bridges, or chromophores.
1. A chromophore having the structure
wherein, independently at each occurrence, π 1 is absent or a bridge that provides electronic conjugation between D and the remainder of the molecule; π 2 is absent or a bridge that provides electronic conjugation between A and the remainder of the molecule; D is an electron donating group; A is an electron accepting group; X is O or S; R is alkyl, aryl, or heteroalkyl; n=1-4; and the two R groups join together to form a heterocyclic ring with both X groups forming portions of the heterocyclic ring.
2. The chromophore of claim 1 wherein at least one of π 1 , π 2 , D, and A is substituted with at least one halogen, alkyl, aryl, or heteroalkyl group.
3. The chromophore of claim 1 , wherein the D is selected from the group consisting of
and A is selected from the group consisting of
wherein, independently at each occurrence, R 1 is halogen, alkyl, aryl, heteroalkyl; R 2 is hydrogen, alkyl, aryl, heteroalkyl; Y═O, S, or N—R; m=0-3; p=0-3; and q=0-1.
4. The chromophore of claim 1 , wherein the heterocyclic ring is a 5-, 6-, 7-, or 8-membered ring.
5. The chromophore of claim 1 , wherein the heterocyclic ring has the structure
wherein R 2 is independently at each occurrence an alkyl, heteroalkyl, aryl, or hetereoaryl; and wherein any two of R 2 may be bonded together to form a ring.
6. The chromophore of claim 1 , wherein the heterocyclic ring has the structure
and R 2 is absent or independently at each occurrence —CH 2 OH, —CH 2 OSiR 3 ; —CH 2 —(OCH 2 CH 2 ) m —OH, or —CH 2 —(OCH 2 CH 2 ) m —OR; and m=1-4.
7. The chromophore of claim 1 , wherein π 1 and π 2 include —CH═CH—.
8. The chromophore of claim 1 , wherein the chromophore has the structure
9. An electro-optic polymer comprising the chromophore of claim 1 , wherein the polymer is a guest-host composite, crosslinked polymer, or a side-chain polymer.
10. The electro-optic polymer of claim 9 , having increased photostability or temperature stability compared to an otherwise equivalent structure when the two R groups are not joined together.
11. A method, comprising:
a) providing a polymer composite including the structure:
wherein, independently at each occurrence, π 1 is absent or a bridge that provides electronic conjugation between D and the remainder of the molecule; π 2 is absent or a bridge that provides electronic conjugation between A and the remainder of the molecule; D is an electron donating group; A is an electron accepting group; X is O or S; R is alkyl, aryl, or heteroalkyl; n=1-4; and the two R groups join together to form a heterocyclic ring including both X groups; and
b) poling the polymer under an electric field to induce electro-optic activity.
12. The method of claim 11 , wherein the poling includes corona poling or contact poling.
13. The method of claim 11 , wherein at least one of π 1 , π 2 , D, and A is further independently substituted with at least one halogen, alkyl, aryl, or heteroalkyl group.
14. A method, comprising
a) passing light through an electro-optic polymer having a variable index of refraction; and
b) applying a voltage to the electro-optic polymer so that the index of refraction changes; and
wherein the electro-optic polymer includes the structure:
wherein, independently at each occurrence, π 1 is absent or a bridge that provides electronic conjugation between D and the remainder of the molecule; π 2 is absent or a bridge that provides electronic conjugation between A and the remainder of the molecule; D is an electron donating group; A is an electron accepting group; X is O or S; R is alkyl, aryl, or heteroalkyl; n=1-4; and the two R groups join together to form a heterocyclic ring including both X groups.
15. The method of claim 14 , wherein at least one of π 1 , π 2 , D, or A is further independently substituted with at least one halogen, alkyl, aryl, or heteroalkyl group.
16. A optical device comprising: an electro-optic polymer including the chromophore of claim 1 , wherein the device includes an electro-optic Mach-Zehnder modulator, a directional coupler, a phase modulator, a micro resonator, or a micro-ring resonator.