Patent US4378599A successfully refreshed from Google Patents.
US4378599A
Expired / Lapsed
US
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Semiconductor laser having broadband laser gain
Assignee: AT&T Inc
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Filing: 1981-03-03
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Granted: 1983-03-29
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Expires: 2001-03-03
Abstract
Abstract Broadband laser gain is obtained in semiconductor materials by pumping an ultra-short laser cavity with picosecond excitation pulses. The broadband laser gain is used to provide picosecond laser radiation energy covering a wide spectrum of frequencies.
Inventors
- 👤 Theodoor C. Damen
- 👤 Michel A. Duguay
- 👤 Julian Stone
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 19:46
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/04; H01S5/041; H01S5/10; H01S5/18; H01S5/183; H01S5/18361; H01S5/18369
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
109 words
A laser which comprises: a semiconductor material (1) having substantially parallel sides, said material being disposed between reflecting surfaces (2 and 3); means (15 and 16) for exciting said semiconductor material with a high intensity excitation pulse having an ultra-short time duration, the intensity of said excitation pulse being at least as great as 3 GW/cm 2 , the time duration of said excitation pulse being less than or substantially equal to one picosecond, the thickness of said laser semiconductor material being less than or substantially equal to 1 μm, whereby a broadband laser gain at energies above the energy difference between the conduction and valence bands is produced.
Claim 2
Dependent Claim
109 words
A laser which comprises: a semiconductor material (1) having substantially parallel sides, said material being disposed between reflecting surfaces (2 and 3); means (15 and 16) for exciting said semiconductor material with a high intensity excitation pulse having an ultra-short time duration, the intensity of said excitation pulse being at least as great as 3 GW/cm 2 , the time duration of said excitation pulse being less than or substantially equal to one picosecond, the thickness of said laser semiconductor material being less than or substantially equal to 1 μm, whereby a broadband laser gain at energies above the energy difference between the conduction and valence bands is produced.
Claim 3
Dependent Claim
41 words
A laser in accordance with claim 1 wherein said means for exciting said laser semiconductor material includes a source of laser radiation, said radiation having photons with energy larger than the bandgap between the valence and conduction bands in said material.
Claim 4
Dependent Claim
27 words
A laser in accordance with claim 2 wherein said laser material is a binary III-V or II-VI semiconductor material or a ternary or quaternary III-V semiconductor material.
Claim 5
Dependent Claim
13 words
A laser in accordance with claim 3 wherein said laser material is GaAs.
Claim 6
Dependent Claim
13 words
A laser in accordance with claim 4 wherein said laser material is CdSe.
Claim 7
Dependent Claim
16 words
A laser in accordance with claim 3 wherein said alloy is a quaternary compound of InGaAsP.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-03-28 | 1986-09-27 | 1987-03-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-03-28 | 1990-09-27 | 1991-03-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-03-28 | 1994-09-27 | 1995-03-29 | $7700.00 | Window Closed / Lapsed |