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:
Jul. 02, 2019
Filed:
May. 07, 2015
Sharp Kabushiki Kaisha, Sakai, Osaka, JP;
The University of Tokyo, Bunkyo-ku, Tokyo, JP;
Teruhisa Kotani, Sakai, JP;
Yasuhiko Arakawa, Bunkyo-ku, JP;
Sharp Kabushiki Kaisha, Sakai, JP;
The University of Tokyo, Tokyo, JP;
Abstract
A QCL () includes a first electrode (), a first contact layer () that is in contact with the first electrode () and is made of a first compound semiconductor, a second electrode () having a polarity opposite to that of the first electrode (), a second contact layer () that is in contact with the second electrode () and is made of a second compound semiconductor, and an active layer () disposed between the first contact layer () and the second contact layer () and including two or more active layer units. Each of the active layer units includes one or more quantum well layers made of a third compound semiconductor and one or more barrier layers made of a fourth compound semiconductor, and each of the quantum well layers and each of the barrier layers are alternately stacked. The vibrational energies of longitudinal optical phonons of the third compound semiconductor and the fourth compound semiconductor are higher than the vibrational energy of a longitudinal optical phonon of GaAs and lower than or equal to the vibrational energy of a longitudinal optical phonon of AlN.