Coherent light generators – Particular active media – Semiconductor
Patent
1993-05-06
1994-02-15
Epps, Georgia Y.
Coherent light generators
Particular active media
Semiconductor
372 46, 372 20, 372 75, H01S 319
Patent
active
052873773
ABSTRACT:
The present invention is the use of coupled quantum wells in the active region of a semiconductor laser to modulate the frequency and amplitude of the light output of the laser. In a particular embodiment of the present invention the coupled quantum wells are contained in a graded index of refraction semiconductor double heterostructure laser. The active region of this tunable laser consists of two quantum wells having a width of approximately 50 Angstroms or less which are separated by a barrier layer having a width of approximately 20 Angstroms or less. The quantum well material is intrinsic GaAs and the barrier layer is Al.sub.x Ga.sub.1-x As wherein x=0.23. The active region is surrounded by the double heterostructure in which one side is doped p-type and the second side is doped n-type. The resulting laser is a p-i-n type structure. A reverse bias with respect to the flat band voltage of the p-i-n structure is applied across the p-i-n structure which modulates both the frequency and the intensity of the laser output. The tunable laser is pumped with a variety of conventional means, including both electrical and optical pumping. The modulation of the wavelength is approximately linear over a 1.5 volt operating range. A tunable laser, such as the present invention, having an output wavelength modulated by an electric field is useful in the field of optical communications and computing.
REFERENCES:
patent: 4700353 (1987-10-01), Van Gieson et al.
patent: 4823352 (1989-04-01), Sugimoto
patent: 4885753 (1989-12-01), Okai et al.
patent: 4999842 (1991-03-01), Huang et al.
patent: 4999844 (1991-03-01), Imamoto
patent: 5023879 (1991-06-01), Wang et al.
patent: 5068867 (1991-11-01), Hasenberg et al.
S. Charbonneau et al. "Transformation of Spatially Direct to Spatially Indirect Excitons . . . " Physical Review B, vol. 38, No. 9, Sep. 15, 1988, pp. 6287-6290.
N. N. Islam et al. "Electroabsorption in GaAS/AlGaAs Coupled Quantum Well Waveguides", Appl. Phys. Lett. 50 (16) Apr. 20, 1987, pp. 1098-1100.
T. Fukuzawa, et al. "Phase Transition of an Exciton System in GaAs Coupled Quantum Wells", Physical Review Letters, vol. 64, No. 25 Jun. 18, 1990, pp. 3066-3069.
Alexandrou, "Electric-Field Effects On Exciton Lifetimes", Phys. Rev. B., Nov. 15, 1990 vol. 42, No. 14, pp. 9225-9228.
Fukuzawa, "Phase Transition of An Exciton System", Phys. Rev. Lett., Jun. 18, 1990, vol. 64, No. 25, pp. 3066-3069.
Chen, "Effect of Electric Fields On Exitons", Phys. Rev. B., Sep. 15, 1987 vol. 36, No. 8, pp. 4562-4565.
Islam, "Electroabsorption in GaAs/AlGaAs Coupled Quantum Wells", Appl. Phys. Lett. vol. 50(16), Apr. 20, 1987, pp. 1098-1100.
Mendez, "Effect of An Electric Field On The Luminescence of GaAs Quantum Wells", Phys. Rev. (B), vol. 26, No. 12, Dec. 15, 1982, pp. 7101-7104.
Zayhowski, "Stark Effect In Al.sub.x Ga.sub.1-x As/GaAs Coupled Quantum Wells", Appl. Phys. Lett., vol. 50, No. 21, May 25, 1987, pp. 1518-1520.
Fukuzawa Tadashi
Liu Ling Y.
Mendez Emilio E.
Epps Georgia Y.
Harper Blaney
International Business Machines - Corporation
Trepp Robert M.
LandOfFree
Coupled quantum well tunable laser does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Coupled quantum well tunable laser, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Coupled quantum well tunable laser will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1213327