Optical: systems and elements – Optical amplifier – Particular active medium
Patent
1991-07-30
1992-09-29
Moskowitz, Nelson
Optical: systems and elements
Optical amplifier
Particular active medium
357 30, 372 45, H01S 325, H01S 319, C02F 300
Patent
active
051518180
ABSTRACT:
An optical amplifier with a semiconductor body includes a layer structure grown on a substrate, with an active layer between two cladding layers, and a strip-shaped amplification region bounded by two end faces of low reflection which form the input and output faces for the radiation to be amplified. The active layer has a number of quantum well (QW) layers with direct band transition, and separated by barrier layers of a different semiconductor material, a first portion of the QW layers being under tensile stress. Another portion of the layers forming part of the active layer is under compressive stress. Owing to the compressive stress present locally in the amplification region, the TE-mode is more strongly amplified there than the TM-mode, while in the tensile portion of the amplification region the TM-mode is more strongly amplified than the TE-mode. This results in a polarization-insensitive amplifier with higher stress and thus with a large amplification at a relatively low current. In one embodiment, both portions of QW layers are within one stack of layers containing the amplification region. In another embodiment both portions are positioned in different stacks that are located next to each other each adjoining a different end zone of the amplification region. In the latter, independent adjustment of the TE and TM amplification profiles is possible.
REFERENCES:
patent: 4612645 (1986-09-01), Liu
patent: 4663761 (1987-05-01), Barnard et al.
patent: 4685108 (1987-08-01), Seymour et al.
patent: 4804639 (1989-04-01), Yablonovitch
patent: 4935935 (1990-06-01), Reed et al.
patent: 4952792 (1990-08-01), Caridi
patent: 5011550 (1991-04-01), Konushi et al.
Melman et al.; "In GaAs/GaAs Strained Quantum Wells . . . "Appl. Phys. Lett., vol. 55, No. 14, pp. 1436-8 Oct. 28, 1989; abst. only provided.
Schblerkamp et al.; "Quantum-Well Starts . . . Tension"; Phys. Rev. B. Covelens. Matter, Vol. 40, #5, pp. 3077-80 Aug. 15, 1989, abst. only.
M. Houng; "the Strain Effect on . . . Quantum Wells"; 1989, Superlatices Microstruct., vol. 6, #4, pp. 421-6; abst. only.
Mailhiat et al.; "Effects of Compressive Uniaxial Stress . . . "; Phys. Rev. B., vol. 36, #5, pp. 2942-5, Aug. 15, 1987. abst. only.
Thijs Petrus J. A.
Tiemeijer Lukas F.
Biren Steven R.
Moskowitz Nelson
U.S. Philips Corp.
LandOfFree
Semiconductor optical amplifier does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Semiconductor optical amplifier, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Semiconductor optical amplifier will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1973136