Plasmonic nanoparticles as pixels and sub-microsecond switches

• US 10,606,145 B2
• Filed: 10/17/2018
• Issued: 03/31/2020
• Est. Priority Date: 10/18/2017
• Status: Active Grant

• Current Assignee: The Government Of The United States Of America, As Represented By The Secretary Of The Navy
• Original Assignee: The Government Of The United States Of America, As Represented By The Secretary Of The Navy
• Inventors: Fontana, Jake, Greybush, Nicholas J.
• Primary Examiner(s): Wong, Eric
• Application Number:
  US16/163,399
• Publication Number:
  US 20190113824A1
• Time in Patent Office: 531 Days
• Field of Search: 385 40
• CPC Class Codes: G02F 1/0063 Optical properties, e.g. absorption, reflection or birefringence materials for non-linear optics G02F1/355
• CPC Class Codes: G02F 1/0115 in optical fibres
• CPC Class Codes: G02F 1/0118 by controlling the evanescent coupling of light from a fibre into an active, e.g. electro-optic, overlay
• CPC Class Codes: G02F 1/172 based on a suspension of orientable dipolar particles, e.g. suspended particles displays
• CPC Class Codes: G02F 1/195 by using frustrated reflection digital reflection using controlled total internal reflection G02F1/315
• CPC Class Codes: G02F 1/292 by controlled diffraction or phased-array beam steering controlled diffraction for optical switching G02F1/31
• CPC Class Codes: G02F 2201/02 fibre
• CPC Class Codes: G02F 2201/08 light absorbing layer
• CPC Class Codes: G02F 2201/122 having a particular pattern
• CPC Class Codes: G02F 2202/16 conductive
• CPC Class Codes: G02F 2202/36 Micro- or nanomaterials
• CPC Class Codes: G02F 2203/10 plasmon
• CPC Class Codes: H01S 3/067 Fibre lasers

Abstract

Application of an electric field to nanorods can control their alignment, thus providing techniques for ultra-fast switching and optical modulators, for example those that might serve as display indicators.

Claims

1. An electro-optical fluid fiber component comprising:

a fiber component comprising an inlet and an outlet configured to receive and send light, respectively, through the fiber component;

a plurality of nanorods suspended in a fluid contained between the inlet and outlet of the fiber component; and

electrodes configured to apply an electric field to the nanorods sufficient to repeatably alter orientation of the nanorods and thereby modulate passage of the light through the fiber component in a manner corresponding to the nanorod orientation.

2. The electro-optical fluid fiber component of claim 1, further comprising connections to a further network of optical fibers.

11. The component of claim 1, wherein the component is operable at switching speeds of one millisecond or less.

12. The component of claim 1, wherein said plurality of nanorods are suspended as an aerosol.

3. A method of modulating light, comprising:

transmitting light through an electro-optical fluid fiber component comprising a plurality of nanorods suspended in a fluid contained in the fiber component and electrodes configured to apply an electric field to the nanorods sufficient to repeatably alter their orientation, wherein the light passes through the plurality of nanorods;

passing an electric field across the electrodes, thereby modulating the light as it passes through the nanorods, wherein the modulation corresponds to the nanorod orientation.

4. An optical modulator comprising:

at least one pixel comprising a plurality of nanorods suspended in a fluid and configured to receive illumination from an illumination source; and

electrodes configured to apply an electric field to the nanorods sufficient to repeatably alter their orientation in suspension, such that the alteration of nanorod orientation is effective to modulate at least one optical property of the nanorods suspended in the fluid.

5. The optical modulator of claim 4, wherein the pixel is a planar structure.

6. The optical modulator of claim 4, further comprising a substrate supporting the at least one pixel.

7. The optical modulator of claim 4, wherein the modulation is accomplished solely via alternation of the orientation of the nanorods.

8. The optical modulator of claim 4, wherein the modulator is part of a light communications network.

9. The optical modulator of claim 4, wherein the nanorods are suspended in a liquid and contained on a substrate.

10. The optical modulator of claim 9, wherein the liquid is toluene.

13. The optical modulator of claim 4, wherein said plurality of nanorods are suspended as an aerosol.

14. The optical modulator of claim 4, wherein a state of nanorod alignment is controllable by varying the magnitude and/or frequency of the electric field.