The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 21, 1976
Filed:
Mar. 07, 1975
Raymond Dingle, Summit, NJ (US);
Charles Howard Henry, New Providence, NJ (US);
Bell Telephone Laboratories, Incorporated, Murray Hill, NJ (US);
Abstract
Described is a heterostructure semiconductor laser comprising a pair of wide bandgap layers having an active region sandwiched therebetween characterized in that the active region includes a plurality of thin narrow bandgap active layers interleaved with a plurality of thin relatively wider bandgap passive layers. The passive layers are thin enough (e.g., about 10-500 Angstroms) to permit electrons to distribute among the active layers either by tunneling through, or by hopping over, the energy barriers created by the passive layers. The active layers are thin enough (e.g., about 10-500 Angstroms) to separate the quantum levels of electrons confined therein. These lasers exhibit wavelength tunability by changing the thickness of the active layers. Also described is the possibility of threshold reductions resulting from modification of the density of electron states.