US5040186A
Expired / Lapsed
US
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InP-based quantum-well laser
Assignee: Nokia Bell Labs
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Filing: 1990-08-07
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Granted: 1991-08-13
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Expires: 2010-08-07
Abstract
Abstract Disclosed is a graded index separate confinement heterostructure quantum well (GRIN-SCH QW) laser with continuously graded, substantially index matched InGaAsP confinement layer. The inventive device is well adapted for high power output in the wavelength region 1.2-1.68 μm. In particular, it can readily be designed to have an output wavelength that makes it suitable as pump source for Er-doped optical fiber amplifiers. A method of manufacturing a laser according to the invention is also disclosed.
Inventors
- 👤 Ralph A. Logan
- 👤 Tawee Tanbun-ek
- 👤 Henryk Temkin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 11:41
CPC Classifications
H; H10; H10H; H10H20/00; H10H20/80; H10H20/81; H10H20/811; H10H20/812; B; B82; B82Y; B82Y20/00; H01; H01S; H01S5/00; H01S5/30; H01S5/34; H01S5/343; H01S5/34313; H01S5/3434; H10H20/01; H10H20/011; H10H20/013; H01S5/20; H01S5/2004; H01S5/2009; H01S5/3403; H01S5/3406; H01S5/3409; H01S5/34306
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
90 words
Apparatus comprising a semiconductor laser having an emission wavelength in the range 1.2-1.68 μm and being capable of room temperature CW emission, the laser comprising; (a) a confinement layer comprising GaInAsP; and (b) an active region comprising one or more quantum wells; wherein (c) the composition of at least a major portion of the material of the confinement layer varies continuously as a function of distance from the active region, with the variation selected such that at least the portion of the confinement layer is substantially lattice matched to InP.
Claim 2
Dependent Claim
90 words
Apparatus comprising a semiconductor laser having an emission wavelength in the range 1.2-1.68 μm and being capable of room temperature CW emission, the laser comprising; (a) a confinement layer comprising GaInAsP; and (b) an active region comprising one or more quantum wells; wherein (c) the composition of at least a major portion of the material of the confinement layer varies continuously as a function of distance from the active region, with the variation selected such that at least the portion of the confinement layer is substantially lattice matched to InP.
Claim 3
Dependent Claim
15 words
Apparatus of claim 1, wherein the material of at least one quantum well is strained.
Claim 4
Dependent Claim
78 words
Apparatus of claim 2, wherein the active region comprises at least two quantum wells with a barrier layer therebetween, wherein the material of the at least two quantum wells is strained, the quantum well strain having a first sense, and wherein furthermore the material of the barrier layer is strained, the barrier layer strain being of a sense opposite to the first sense, whereby the overall strain of the active region is maintained at a relatively low level.
Claim 5
Dependent Claim
23 words
Apparatus of claim 1, wherein the laser is capable of CW emission at room temperature of at least 50 mW of optical power.
Claim 6
Dependent Claim
49 words
Apparatus of claim 1, wherein the confinement layer comprises a first and a contiguous second sublayer, with the composition of the material in the first sublayer varying at a first rate, and the composition of the second sublayer varying at a second rate that differs from the first rate.
Claim 7
Dependent Claim
73 words
Apparatus of claim 1, wherein the apparatus is an optical fiber communication system that comprises (i) a length of rare earth-doped optical fiber; (ii) means for causing an electrical current to flow through the laser such that the laser has an output radiation, the output radiation having a wavelength in the range 1.2-1.68 μm; and (iii) means for coupling at least a portion of the output radiation into the rare earth-doped optical fiber.
Claim 8
Dependent Claim
11 words
Apparatus of claim 6, wherein the rare earth-doped fiber comprises Er.
Claim 9
Dependent Claim
18 words
Apparatus of claim 2, wherein the material of the at least one quantum well is strained in tension.
Claim 10
Dependent Claim
135 words
An optical fiber communication system that comprises (i) a length of rare earth-doped optical fiber; (ii) an InP-based quantum well laser having an emission wavelength in the range 1.2-1.68 μm; (iii) means for causing an electrical current to flow through the laser such that the laser has a cw output radiation; and (iv) means for coupling at least a portion of the output radiation into the rare earth-doped optical fiber; wherein the laser is such that the material of at least one quantum well is under tensile strain such that Δc/c≧10 -3 , where c is the room temperature equilibrium lattice constant associated with comparison quantum well well material that is lattice matched to InP, and Δc=c-c b , where c b is the room temperature equilibrium lattice constant associated with the quantum well material.
Claim 11
Dependent Claim
135 words
An optical fiber communication system that comprises (i) a length of rare earth-doped optical fiber; (ii) an InP-based quantum well laser having an emission wavelength in the range 1.2-1.68 μm; (iii) means for causing an electrical current to flow through the laser such that the laser has a cw output radiation; and (iv) means for coupling at least a portion of the output radiation into the rare earth-doped optical fiber; wherein the laser is such that the material of at least one quantum well is under tensile strain such that Δc/c≧10 -3 , where c is the room temperature equilibrium lattice constant associated with comparison quantum well well material that is lattice matched to InP, and Δc=c-c b , where c b is the room temperature equilibrium lattice constant associated with the quantum well material.
Claim 12
Dependent Claim
43 words
System of claim 9, wherein the laser comprises at least one confinement layer in contact with the quantum well, with the composition of at least a major portion of the confinement layer varying continuously as a function of distance from the quantum well.
References Cited (Backward Citations)
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| 3.5 Years (Year 4) | 1994-08-12 | 1995-02-11 | 1995-08-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-08-12 | 1999-02-11 | 1999-08-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-08-12 | 2003-02-11 | 2003-08-13 | $7700.00 | Window Closed / Lapsed |