US4597638A
Expired / Lapsed
US
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Nonlinear optical apparatus
Assignee: Nokia Bell Labs
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Filing: 1983-12-30
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Granted: 1986-07-01
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Expires: 2003-12-30
Abstract
Abstract A nonlinear optical apparatus is provided with a multiple layer heterostructure made from alternate layers of a charge carrier semiconductor material having a narrow bandgap energy, and a charge barrier material having a wider bandgap energy than the charge carrier material. The layers are deposited one upon the other in substantially flat planes forming a series of potential barriers. The potential barriers are capable of confining charge carriers which arise within the layers of the charge carrier semiconductor material to remain substantially therein. The optical absorption coefficient of the multiple layer heterostructure exhibits at least one sharp resonant optical absorption peak near the semiconductor material bandgap absorption. A light source is restricted to provide a beam of light photons of energy near the energy of the sharp resonant optical absorption peak for promoting production of charge carriers within the charge carrier semiconductor material. The light photons are directed into the multiple layer heterostructure so that the light photons may saturate the optical absorption coefficient and thereby cause the index of refraction of the multiple layer heterostructure to vary with incident light intensity.
Inventors
- 👤 Daniel S. Chemla
- 👤 David A. B. Miller
- 👤 Peter W. Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 11:38
CPC Classifications
B; B82; B82Y; B82Y20/00; G; G02; G02F; G02F1/00; G02F1/01; G02F1/015; G02F1/017; G02F1/01716; G02F1/21; G02F1/218; G02F1/35; G02F1/355; G02F1/3556; G02F3/00; G02F3/02; G02F3/024; G02F1/29; G02F1/31; G02F1/313; G02F1/3137; G02F1/3515
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
190 words
A nonlinear optical apparatus comprising: a multiple layer heterostructure having first and second material layers having first and second bandgaps, respectively, and a semiconductor layer having a third bandgap and being positioned between said material layers, the bottom of the conduction band of said semiconductor layer being below the bottom of the conduction bands of said material layers, and the top of the valence bands of said semiconductor layer being above the tops of the valence bands of said material layers, the thickness of said semiconductor layer being sufficient for carrier confinement effects within said semiconductor layer to influence the optical properties of said multiple layer heterostructure, and said multiple layer heterostructure being such that exciton absorption and interband absorption are resolved at room temperature; means for illuminating said multiple layer heterostructure with light photons having an optical frequency capable of causing absorption transitions between energy levels, said energy levels being influenced by said carrier confinement effects; and means for varying an illumination intensity within said multiple layer heterostructure in order to vary an optical absorption and an index of refraction of said multiple layer heterostructure for said light photons.
Claim 2
Dependent Claim
190 words
A nonlinear optical apparatus comprising: a multiple layer heterostructure having first and second material layers having first and second bandgaps, respectively, and a semiconductor layer having a third bandgap and being positioned between said material layers, the bottom of the conduction band of said semiconductor layer being below the bottom of the conduction bands of said material layers, and the top of the valence bands of said semiconductor layer being above the tops of the valence bands of said material layers, the thickness of said semiconductor layer being sufficient for carrier confinement effects within said semiconductor layer to influence the optical properties of said multiple layer heterostructure, and said multiple layer heterostructure being such that exciton absorption and interband absorption are resolved at room temperature; means for illuminating said multiple layer heterostructure with light photons having an optical frequency capable of causing absorption transitions between energy levels, said energy levels being influenced by said carrier confinement effects; and means for varying an illumination intensity within said multiple layer heterostructure in order to vary an optical absorption and an index of refraction of said multiple layer heterostructure for said light photons.
Claim 3
Dependent Claim
24 words
A nonlinear optical apparatus as in claim 1 further comprising: a Fabry-Perot cavity and said multiple layer heterostructure is located inside said Fabry-Perot cavity.
Claim 4
Dependent Claim
20 words
A nonlinear optical apparatus as in claim 2 wherein said Fabry-Perot cavity is tuned to make a bistable optical device.
Claim 5
Dependent Claim
19 words
A nonlinear optical apparatus as in claim 2 wherein said Fabry-Perot cavity is tuned to make an optical amplifier.
Claim 6
Dependent Claim
20 words
A nonlinear optical apparatus as in claim 9 wherein said Fabry-Perot cavity is tuned to make a nonlinear optical device.
Claim 7
Dependent Claim
29 words
A nonlinear optical apparatus as in claim 2 wherein said Fabry-Perot cavity is made from two mirrors formed by shaping and treating the exterior of said multiple layer heterostructure.
Claim 8
Dependent Claim
17 words
A nonlinear optical apparatus as in claim 1 wherein said multiple layer heterostructure is made using GaAs.
Claim 9
Dependent Claim
17 words
A nonlinear optical apparatus as in claim 1 wherein said multiple layer heterostructure is made using AlGaAs.
Claim 10
Dependent Claim
17 words
A nonlinear optical apparatus as in claim 1 wherein said multiple layer heterostructure is made using InGaAs.
Claim 11
Dependent Claim
17 words
A nonlinear optical apparatus as in claim 1 wherein said multiple layer heterostructure is made using InGaAlAs.
Claim 12
Dependent Claim
17 words
A nonlinear optical apparatus as in claim 1 wherein said multiple layer heterostructure is made using InGaAsP.
Claim 13
Dependent Claim
17 words
A nonlinear optical apparatus as in claim 1 wherein said multiple layer heterostructure is made using HgCdTe.
Claim 14
Dependent Claim
17 words
A nonlinear optical apparatus as in claim 1 wherein said multiple layer heterostructure is made using Si.
Claim 15
Dependent Claim
17 words
A nonlinear optical apparatus as in claim 1 wherein said multiple layer heterostructure is made using Ge.
Claim 16
Dependent Claim
17 words
A nonlinear optical apparatus as in claim 1 wherein said multiple layer heterostructure is made using GaSb.
Claim 17
Dependent Claim
17 words
A nonlinear optical apparatus as in claim 1 wherein said multiple layer heterostructure is made using AlGaSb.
Claim 18
Dependent Claim
21 words
A nonlinear optical apparatus as in claim 1 wherein said means for illuminating said multiple layer heterostructure comprises an optical waveguide.
Claim 19
Dependent Claim
29 words
A nonlinear optical apparatus as in claim 1 wherein said means for varying an illumination intensity comprises an optical waveguide arranged to direct light into said multiple layer heterostructure.
Claim 20
Dependent Claim
28 words
A nonlinear optical apparatus as in claim 1 further comprising a substrate in which both the multiple layer heterostructure and a laser diode are mounted on said substrate.
Claim 21
Independent Claim
189 words
A method for controlling the intensity of an output light beam comprising the steps of: directing at least one light beam into a multiple layer heterostructure so that it exits as said output light beam; controlling the optical absorption and index of refraction of said multiple layer heterostructure by controlling the illumination intensity within said multiple layer heterostructure in order to control the intensity of said output light beam; said multiple layer heterostructure having first and second material layers having first and second bandgaps, respectively, and a semiconductor layer having a third bandgap and being positioned between said material layers, the bottom of the conduction band of said semiconductor layer being below the bottom of the conduction bands of said material layers, and the top of the valence bands of said semiconductor layer being above the tops of the valence bands of said material layers, the thickness of said semiconductor layer being sufficient for carrier confinement effects within said semiconductor layer to influence the optical properties of said multiple layer heterostructure, and said multiple layer heterostructure being such that exciton absorption and interband absorption are resolved at room temperature.
Claim 22
Independent Claim
189 words
A method for controlling the intensity of an output light beam comprising the steps of: directing at least one light beam into a multiple layer heterostructure so that it exits as said output light beam; controlling the optical absorption and index of refraction of said multiple layer heterostructure by controlling the illumination intensity within said multiple layer heterostructure in order to control the intensity of said output light beam; said multiple layer heterostructure having first and second material layers having first and second bandgaps, respectively, and a semiconductor layer having a third bandgap and being positioned between said material layers, the bottom of the conduction band of said semiconductor layer being below the bottom of the conduction bands of said material layers, and the top of the valence bands of said semiconductor layer being above the tops of the valence bands of said material layers, the thickness of said semiconductor layer being sufficient for carrier confinement effects within said semiconductor layer to influence the optical properties of said multiple layer heterostructure, and said multiple layer heterostructure being such that exciton absorption and interband absorption are resolved at room temperature.
References Cited (Backward Citations)
US3953810A
Cited
US4093344A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1989-06-30 | 1989-12-30 | 1990-07-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-06-30 | 1993-12-30 | 1994-07-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-06-30 | 1997-12-30 | 1998-07-01 | $7700.00 | Window Closed / Lapsed |