Plasmonic switch device and method

Patent metadata

Field	Value
Publication number	US-2016349594-A1
Application number	US-201515110680-A
Country	US
Kind code	A1
Filing date	Jan 9, 2015
Priority date	Jan 10, 2014
Publication date	Dec 1, 2016
Grant date	—

Abstract

A plasmonic switching device and method of providing a plasmonic switching device. An example device includes a resonant cavity and an electromagnetic radiation feed arranged to couple electromagnetic radiation into the resonant cavity and at least one plasmonic mode. The resonant cavity is arranged to be switchable between: a first state in which the resonant cavity has an operational characteristic selected to allow resonance of the electromagnetic radiation at a frequency of the at least one plasmonic mode; and a second state in which the operational characteristic of the resonant cavity is adjusted to inhibit resonance of the electromagnetic radiation at a frequency of the at least one plasmonic mode.

First claim

1 . A plasmonic switching device comprising:
a resonant cavity formed between surfaces, one of said surfaces comprising a plasmonic system operable to support at least one plasmonic mode; an electromagnetic radiation feed arranged to couple electromagnetic radiation into said resonant cavity and said at least one plasmonic mode; wherein said resonant cavity is arranged to be switchable between: a first state in which said resonant cavity has an operational characteristic selected to allow resonance of said electromagnetic radiation at a frequency of said at least one plasmonic mode such that excitation of said at least one plasmonic mode is inhibited in said plasmonic system; and a second state in which said operational characteristic of said resonant cavity is adjusted to inhibit resonance of said electromagnetic radiation at a frequency of said at least one plasmonic mode such that said at least one plasmonic mode is excited in said plasmonic system.

2 . The plasmonic switching device according to claim 1 , wherein said plasmonic system surface comprises an interface between a metal and a dielectric.

3 . The plasmonic switching device according to claim 2 , wherein said operational characteristic comprises: reflectivity of at least one of said surfaces of said cavity.

4 . The plasmonic switching device according to claim 3 , wherein one of said surfaces is configured to have a variable effective refractive index and the resonance condition of said resonant cavity is changed as said effective reflectivity of said surface is varied.

5 . The plasmonic switching device according to claim 4 , wherein said operational characteristic comprises: at least one effective dimension of said cavity.

6 . The plasmonic switching device according to claim 5 , wherein said dimension comprises an effective spacing between said surfaces.

7 . The plasmonic switching device according to claim 6 , wherein said spacing between said surfaces comprises a dielectric configured to have a variable effective refractive index.

8 . The plasmonic switching device according to claim 7 , wherein said refractive index varies upon application of a voltage or optical field across said dielectric enabling refractive index modulation stemming from an increase in carrier concentration in said dielectric.

9 . The plasmonic switching device according to claim 8 , wherein said dielectric comprises a multilayer structure formed from at least one of: Indium Tin Oxide, Hafnium Oxide, Gold, Copper, or Silver.

10 . The plasmonic switching device according to claim 9 , wherein said electromagnetic radiation feed comprises: a source of electromagnetic radiation which enters said cavity via at least one opening provided in one of said surfaces, said opening being arranged such that photons scattered from said opening are coupleable to plasmons at said plasmonic system.

11 . The plasmonic switching device according to claim 10 , wherein said at least one opening is provided in said surface comprising said plasmonic system.

12 . The plasmonic switching device according to claim 10 , wherein said at least one opening is configured symmetrically within said device such that excitation of said plasmonic mode in said device is symmetrical.

13 . The plasmonic switching device according to claim 10 , wherein said at least one opening is arranged to have different dimensions to another of said at least one opening, such that excitation of said plasmonic mode in said device is asymmetrical.

14 . The plasmonic switching device according to claim 10 , wherein said device further comprises: a plasmonic mode detector.

15 . A method of providing a plasmonic switching device comprising:
forming a resonant cavity between surfaces, one of said surfaces comprising a plasmonic system operable to support at least one plasmonic mode; arranging an electromagnetic radiation feed to couple electromagnetic radiation into said resonant cavity and said at least one plasmonic mode; arranging said resonant cavity to be switchable between: a first state in which said resonant cavity has an operational characteristic selected to allow resonance of said electromagnetic radiation at a frequency of said at least one plasmonic mode such that excitation of said at least one plasmonic mode is inhibited in said plasmonic system; and a second state in which said operational characteristic of said resonant cavity is adjusted to inhibit resonance of said electromagnetic radiation at a frequency of said at least one plasmonic mode such that said at least one plasmonic mode is excited in said plasmonic system.

16 - 48 . (canceled)

49 . A switching device comprising:
a resonant cavity formed between surfaces; and an electromagnetic radiation feed arranged to couple electromagnetic radiation into the resonant cavity; wherein the resonant cavity is arranged to switch the electromagnetic feed between: a first state in which the resonant cavity has an operational characteristic selected to allow said cavity to be is driven close to resonance such that passage of the electromagnetic feed through the cavity is inhibited; and a second state in which an operational characteristic of the resonant cavity is adjusted to inhibit cavity resonance such that passage of the electromagnetic feed through the cavity is supported.

50 . The method according to claim 15 , wherein one of said surfaces comprises a variable effective refractive index, and wherein a resonance condition of said resonant cavity is changed as said effective reflectivity of said surface is varied.

51 . The method according to claim 15 , further comprising forming an effective spacing between said surfaces of the resonant cavity.

52 . The method according to claim 51 , wherein the effective spacing between said surfaces of the resonant cavity comprises a dielectric having a variable effective refractive index.

53 . The method according to claim 52 , wherein said refractive index varies upon application of a voltage or optical field across said dielectric.

Assignees

• King S College London

Inventors

• Wurtz Gregory
• Zayats Anatoly
• Mcpolin Cillian
• Barbosa Neira Andres David
• Ginzburg Pavel

Classifications

• G02F1/225 Primary

  in an optical waveguide structure · CPC title

• G02F2202/30

  Metamaterials · CPC title

• G02B26/001

  based on interference in an adjustable optical cavity (interference filters G02B5/28; devices or arrangements using multiple reflections in spectrometry or monochromators G01J3/26) · CPC title

• G02F2203/10

  plasmon · CPC title

• G02F1/21

  by interference · CPC title