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US5448080A Expired / Lapsed US ⏱️ 0.0 years remaining

Ultrafast optical switching device having a double-junction multiple quantum well structure

Assignee: Electronics and Telecommunications Research Institute
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Filing: 1994-07-12
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Granted: 1995-09-05
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Expires: 2014-07-12
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Abstract

Abstract Disclosed is an ultrafast optical switching device having two types of multiple quantum well structures to be connected with each other, the device comprising a semi-insulating substrate; and a first and a second multiple quantum well structure formed sequentially on the substrate and united with each other to produce a double-junction multiple quantum well structure. Each of the multiple quantum well structures has nonlinear optical effects and two life time constants present while switching off in the device. One of the life time constants corresponds to a short life time constant to be determined dependent on electrons in the double-junction multiple quantum well structure and the other of the life time constants corresponds to a long life time constant to be determined dependent on holes and lattices therein. The multiple quantum well structures are formed in such a manner that short life time constants thereof may be in-phase with each other and long life time constants thereof may be out-of-phase to each other. The multiple quantum well structures are formed differently from each other in composition.

Inventors

  • 👤 Seon-Gyu Han
  • 👤 Jong-Tai Lee
  • 👤 Byueng-Su Yoo
  • 👤 Tae-Hyung Zyung
  • 👤 Young-Wan Choi
  • 👤 Pyong-Woon Park
  • 👤 El-Hang Lee

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 18:27
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/015; G02F1/017; G02F1/01716; B; B82; B82Y; B82Y20/00; G02F1/01725; G02F1/01733

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 183 words
An ultrafast optical switching device having two types of multiple well structures connected with each other comprising: a semi-insulating substrate; and a first and a second multiple quantum well structure formed sequentially on the substrate and united with each other to produce a double-junction multiple quantum well structure, each of said multiple quantum well structures having nonlinear optical characteristics with two life time constants when switching off in the device, wherein one of said life time constants corresponds to a short life time constant that is determined dependent on the quantity of electrons in the double-junction multiple quantum well structure and the other of said life time constants corresponds to a long life time constant that is determined dependent on the quantity of holes and lattices in the structure; wherein said two multiple quantum well structures are formed in such a manner that said short life time constants thereof may be in-phase with each other and said long life time constants thereof may be out-of-phase to each other; and wherein said multiple quantum well structures are formed differently from each other in composition.
Claim 2
Dependent Claim 183 words
An ultrafast optical switching device having two types of multiple well structures connected with each other comprising: a semi-insulating substrate; and a first and a second multiple quantum well structure formed sequentially on the substrate and united with each other to produce a double-junction multiple quantum well structure, each of said multiple quantum well structures having nonlinear optical characteristics with two life time constants when switching off in the device, wherein one of said life time constants corresponds to a short life time constant that is determined dependent on the quantity of electrons in the double-junction multiple quantum well structure and the other of said life time constants corresponds to a long life time constant that is determined dependent on the quantity of holes and lattices in the structure; wherein said two multiple quantum well structures are formed in such a manner that said short life time constants thereof may be in-phase with each other and said long life time constants thereof may be out-of-phase to each other; and wherein said multiple quantum well structures are formed differently from each other in composition.
Claim 3
Dependent Claim 53 words
The ultrafast optical switching device according to claim 1, wherein said first multiple quantum well structure is comprised of a plurality of Al x1 Ga 1-x1 As/GaAs layers, and said second multiple quantum well structure is composed of a plurality of Al x2 Ga 1-x2 As/GaAs layers, wherein x1 is greater than x2.
Claim 4
Dependent Claim 61 words
The ultrafast optical switching device according to claim 1, wherein said first multiple quantum well structure is comprised of a plurality of Al x1 Ga 1-x1 As/Al y Ga 1-y As layers, and said second multiple quantum well structure is composed of a plurality of Al x2 Ga 1-x2 As/Al y Ga 1-y As layers, wherein x1 is greater than x2.
Claim 5
Dependent Claim 27 words
The ultrafast optical switching device according to claim 2, wherein the Al x1 Ga 1-x1 As layer is thicker than the Al x2 Ga 1-x2 As layer.
Claim 6
Dependent Claim 33 words
The ultrafast optical switching device according to claim 1, wherein the long life time constant of said first multiple quantum well structure is equal to that of said second multiple quantum well structure.
Claim 7
Dependent Claim 22 words
The ultrafast optical switching device according to claim 1, wherein said semi-insulating substrate is etched selectively so as to allow optical transmission.
Claim 8
Dependent Claim 34 words
The ultrafast optical switching device according to claim 1, and further comprising a mirror layer formed between said semi-insulating substrate and said double-junction multiple quantum well structure so as to reflect an input beam.
Claim 9
Dependent Claim 24 words
The ultrafast optical switching device according to claim 1, wherein a thickness of the double-junction multiple quantum well structure is 1 μm or less.

References Cited (Backward Citations)

US5324959A Cited
US5229878A Cited
US5323019A Cited
US5329136A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1998-09-04 1999-03-06 1999-09-05 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2002-09-04 2003-03-06 2003-09-05 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2006-09-04 2007-03-06 2007-09-05 $7700.00 Window Closed / Lapsed

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