US5274246A
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Optical modulation and switching with enhanced third order nonlinearity multiple quantum well effects
Assignee: United States Department of the Air Force
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Filing: 1992-05-04
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Granted: 1993-12-28
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Expires: 2012-05-04
Abstract
Abstract A multiple quantum well arrangement which achieves significantly improved third order optical nonlinearity in a semiconductor device by way of spatially periodic electrodes applied to the semiconductor device. The spatial period of the applied electrodes and the resulting exciton confinement dimension is improved over that of previous multiple quantum well structures and to the Bohr radius range of dimensions for the semicondcutor material by way of av RIGHTS OF THE GOVERNMENT The invention described herein may be manufactured and used by or for the Government of the United States for all governmental purposes without the payment of any royalty.
Inventors
- 👤 Frank K. Hopkins
- 👤 Joseph T. Boyd
- 👤 Howard E. Jackson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 14:27
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/35; G02F1/355; G02F1/3556; B; B82; B82Y; B82Y20/00; G02F1/01; G02F1/015; G02F1/017; G02F1/01791
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
162 words
A multiple quantum well exciton confinement photonic apparatus of voltage determined large third order optical nonlinearity capability comprising the combination of: a substrate member of selected semiconductor material composition; a multiple quantum well modified layer of said semiconductor material formed over a portion of said substrate member; a first layer of electrically insulating dielectric material formed over a portion of said multiple quantum well semiconductor material; electrode array means including a plurality of electrode members disposed in spatial periodicity on said dielectric material adjacent said multiple quantum well semiconductor material layer and held at predetermined polarities and voltage amplitudes with respect to said substrate member for generating exciton confinement periodic regions and enhanced optical nonlinearity effects in said multiple quantum well semiconductor material; said spatial periodicity being of a period substantially equal to a Bohr radius of said semiconductor material; and means including optical input and output port members for communicating light signals to and from said multiple quantum well semiconductor layer.
Claim 2
Dependent Claim
162 words
A multiple quantum well exciton confinement photonic apparatus of voltage determined large third order optical nonlinearity capability comprising the combination of: a substrate member of selected semiconductor material composition; a multiple quantum well modified layer of said semiconductor material formed over a portion of said substrate member; a first layer of electrically insulating dielectric material formed over a portion of said multiple quantum well semiconductor material; electrode array means including a plurality of electrode members disposed in spatial periodicity on said dielectric material adjacent said multiple quantum well semiconductor material layer and held at predetermined polarities and voltage amplitudes with respect to said substrate member for generating exciton confinement periodic regions and enhanced optical nonlinearity effects in said multiple quantum well semiconductor material; said spatial periodicity being of a period substantially equal to a Bohr radius of said semiconductor material; and means including optical input and output port members for communicating light signals to and from said multiple quantum well semiconductor layer.
Claim 3
Dependent Claim
23 words
The apparatus of claim 1 wherein said semiconductor material comprises layers of compound semiconductor alloys incorporating periodic table group III and IV elements.
Claim 4
Dependent Claim
31 words
The apparatus of claim 2 wherein said electrode members comprise regions of increased electrical conductivity with respect to said dielectric material and with respect to material disposed between said electrode members.
Claim 5
Dependent Claim
71 words
The apparatus of claim 3 wherein said electrode members comprise electrical potential controlling individual strip element means disposed across and electrically insulating dielectric material at uniform spatial periods up to an excitonic Bohr radius of said semiconductor material for distorting a conduction band and a valence band in said layer of multiple quantum well semiconductor material into complementary undulating hill and valley patterns having substantially said excitonic Bohr radius spatial period.
Claim 6
Dependent Claim
13 words
The apparatus of claim 4 wherein said electrode members are comprised of metal.
Claim 7
Dependent Claim
15 words
The apparatus of claim 4 wherein said electrode members are comprised of polycrystalline semiconductor material.
Claim 8
Dependent Claim
18 words
The apparatus of claim 1 wherein said electrode members are spaced at intervals of less than thirty microns.
Claim 9
Dependent Claim
12 words
The apparatus of claim 1 wherein said semiconductor material is gallium arsenide.
Claim 10
Dependent Claim
49 words
The apparatus of claim 1 wherein said electrode members are comprised of metal and further including a second layer of electrical insulating material disposed over said metallic electrode members and a layer of metal material disposed over an exposed surface portion of said second layer of electrical insulating material.
Claim 11
Dependent Claim
24 words
The apparatus of claim 9 wherein said second layer of electrical insulating material and said layer of metal material include undulating complementary surface topographies.
Claim 12
Dependent Claim
39 words
The apparatus of claim 1 wherein said electrode members comprise electrically insulating material of differing dielectric constants, and further including a layer of metal disposed over an exposed surface portion of said electrically insulating material of differing dielectric constant.
Claim 13
Dependent Claim
47 words
The apparatus of claim 1 wherein said electrode members comprise physically separated electrical insulating pseudo electrode members having differing dielectric constant from said first electrically insulating dielectric material and further including a layer of metal overlaying said pseudo electrode members and spaces intermediate said pseudo electrode members.
Claim 14
Independent Claim
168 words
A method for providing confined exciton third order nonlinear optical effects in a semiconductor sample incident optical beam comprising the steps of: communicating said optical beam as input signal to a selected one of a transmission mode and a reflection mode beam altering relationship with an optical waveguide received sample of multiple quantum well said semiconductor material; generating within said semiconductor material sample an exciton confinement energy band relationship wherein exciton electrons are concentrated in valley reigons of an uppermost conduction band and exciton holes are concentrated in hill regions of a lowermost valence band; said generating step including disposing said conduction band valley and valence band hill regions within said semiconductor material by applying a spatially periodic electric field generating voltage pattern across a surface region of said semiconductor material; said spatially periodic electric field having a period length up to an excitonic Bohr radius of said semiconductor material; and collecting from said semiconductor material a voltage controlled third order optical nonlinearity effect-altered beam output optical signal.
Claim 15
Independent Claim
168 words
A method for providing confined exciton third order nonlinear optical effects in a semiconductor sample incident optical beam comprising the steps of: communicating said optical beam as input signal to a selected one of a transmission mode and a reflection mode beam altering relationship with an optical waveguide received sample of multiple quantum well said semiconductor material; generating within said semiconductor material sample an exciton confinement energy band relationship wherein exciton electrons are concentrated in valley reigons of an uppermost conduction band and exciton holes are concentrated in hill regions of a lowermost valence band; said generating step including disposing said conduction band valley and valence band hill regions within said semiconductor material by applying a spatially periodic electric field generating voltage pattern across a surface region of said semiconductor material; said spatially periodic electric field having a period length up to an excitonic Bohr radius of said semiconductor material; and collecting from said semiconductor material a voltage controlled third order optical nonlinearity effect-altered beam output optical signal.
Claim 16
Dependent Claim
34 words
The method of claim 13 wherein said communicating, generating, and collecting steps comprise one-dimensional exciton confinement in said semiconductor sample and further including first additional steps comprising exciton confinement in a second physical dimension.
Claim 17
Dependent Claim
18 words
The method of claim 14 further including second additional steps comprising exciton confinement in a third physical dimension.
Claim 18
Dependent Claim
12 words
The method of claim 13 wherein said steps comprise beam amplitude modulation.
Claim 19
Dependent Claim
13 words
The method of claim 13 wherein said beam altering comprises beam on-and-off switching.
Claim 20
Dependent Claim
26 words
The method of claim 13 wherein said generating step includes energizing an array of semiconductor material surface-proximate electrode members with a predetermined pattern of electrode voltages.
Claim 21
Dependent Claim
25 words
The method of claim 18 wherein said generating step also includes disposing said electrodes at intervals equal to, or less than, said excitonic Bohr radius.
Claim 22
Dependent Claim
45 words
The method of claim 13 wherein said semiconductor sample includes one of an otherwise induced and an inherent therein third order nonlinear optical characteristic and wherein said communicating, generating, and collecting steps providing nonlinearity are supplementary to said otherwise induced and inherent third order nonlinearity.
References Cited (Backward Citations)
US4796068A
Cited
US4894691A
Cited
US4828368A
Cited
US4933731A
Cited
US4880297A
Cited
US4941025A
Cited
US4903101A
Cited
US4957337A
Cited
US4873439A
Cited
US4905056A
Cited
US5130690A
Cited
US4923264A
Cited
US5053843A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-12-27 | 1997-06-28 | 1997-12-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-12-27 | 2001-06-28 | 2001-12-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-12-27 | 2005-06-28 | 2005-12-28 | $7700.00 | Window Closed / Lapsed |