US3982207A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Quantum effects in heterostructure lasers
Assignee: AT&T Inc
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Filing: 1975-03-07
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Granted: 1976-09-21
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Expires: 1995-03-07
Abstract
Abstract Described is a heterostructure semiconductor laser comprising a pair of wide bandgap layers having an active region sandwiched therebetween characterized in that the active region includes a plurality of thin narrow bandgap active layers interleaved with a plurality of thin relatively wider bandgap passive layers. The passive layers are thin enough (e.g., about 10-500 Angstroms) to permit electrons to distribute among the active layers either by tunneling through, or by hopping over, the energy barriers created by the passive layers. The active layers are thin enough (e.g., about 10-500 Angstroms) to separate the quantum levels of electrons confined therein. These lasers exhibit wavelength tunability by changing the thickness of the active layers. Also described is the possibility of threshold reductions resulting from modification of the density of electron states.
Inventors
- 👤 Raymond Dingle
- 👤 Charles Howard Henry
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 07:30
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/30; H01S5/34; H01S5/343; H01S5/34313; B; B82; B82Y; B82Y20/00; H01S5/3432; Y; Y10; Y10S; Y10S148/00; Y10S148/067; Y10S148/169
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
119 words
In a heterostructure laser, a multilayered semiconductor body comprising: first and second wide bandgap layers, an active region situated between and contiguous with said first and second layers, CHARACTERIZED IN THAT, said active region includes a plurality of active layers and a plurality of passive layers interleaved with one another, said passive layers having a wider bandgap than said active layers, thereby forming energy barriers between said active layers, said passive layers being sufficiently thin to permit carriers to tunnel through or hop over said energy barriers when said body is suitably pumped, and said active layers being sufficiently thin to produce quantum effects in said body including separating the discrete energy levels of carriers in said active layers.
Claim 2
Dependent Claim
119 words
In a heterostructure laser, a multilayered semiconductor body comprising: first and second wide bandgap layers, an active region situated between and contiguous with said first and second layers, CHARACTERIZED IN THAT, said active region includes a plurality of active layers and a plurality of passive layers interleaved with one another, said passive layers having a wider bandgap than said active layers, thereby forming energy barriers between said active layers, said passive layers being sufficiently thin to permit carriers to tunnel through or hop over said energy barriers when said body is suitably pumped, and said active layers being sufficiently thin to produce quantum effects in said body including separating the discrete energy levels of carriers in said active layers.
Claim 3
Dependent Claim
20 words
The body of claim 1 wherein each of said passive and active layers are less than about 500 Angstroms thick.
Claim 4
Dependent Claim
14 words
The body of claim 2 wherein said active layers are about 50 Angstroms thick.
Claim 5
Dependent Claim
10 words
The body of claim 2 wherein said layers comprise AlGaAs.
Claim 6
Dependent Claim
23 words
The body of claim 4 wherein said active layers comprise GaAs and said passive layers comprise Al x Ga 1-x As, x> O.
Claim 7
Dependent Claim
36 words
The body of claim 4 wherein said active layers comprise Al x Ga 1-x As, x ≧O and said passive layers comprise Al y Ga 1-y As 1-z P z , y > x, z ≧O.
Claim 8
Dependent Claim
15 words
The body of claim 2 including means for pumping said body above the lasing threshold.
Claim 9
Dependent Claim
16 words
The body of claim 7 wherein said pumping means includes a p-n junction within said body.
Claim 10
Dependent Claim
29 words
The body of claim 8 wherein said first and second layers have opposite conductivity types and said active and passive layers have the same conductivity type as one another.
Claim 11
Dependent Claim
17 words
The body of claim 9 including means for forward biasing said p-n junction above the lasing threshold.
References Cited (Backward Citations)
US3911376A
Cited
US3691476A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-09-21 | 1980-03-22 | 1980-09-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-09-21 | 1984-03-22 | 1984-09-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-09-21 | 1988-03-22 | 1988-09-21 | $7700.00 | Window Closed / Lapsed |