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:
Jun. 13, 2000
Filed:
Mar. 24, 1998
Paul H Shen, North Potomac, MD (US);
Jagadeesh Pamulapati, Washington, DC (US);
Mitra Dutta, Raleigh, NC (US);
The United States of America as represented by the Secretary of the Army, Washington, DC (US);
Abstract
A semiconductor waveguide modulator that is polarization insensitive/independent at bias variations for any chosen wavelength. The modulator of the present invention employs a novel type of strained semiconductor quantum well (QW) structure that exhibits bias independent, heavy-hole and light hole degeneracy. This effect is achieved by inserting one or two thin layers of highly tensile, strained materials in a specific position within the QW. By adjusting the thickness and the position of the highly tensile strained layers, the quantum confined Stark effect (QCSE) for the heavy hole and light hole can be engineered separately to control the bias dependent polarization properties. The present invention has applications, for example, in optoelectronic devices in the areas of telecommunications, optical signal processing, scanning and displays.