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:
May. 05, 2015
Filed:
Aug. 01, 2012
Hideki Hirayama, Asaka, JP;
Tsung-tse Lin, Sendai, JP;
Hideki Hirayama, Asaka, JP;
Tsung-Tse Lin, Sendai, JP;
Riken, Saitama, JP;
Abstract
[PROBLEM] To manufacture a quantum cascade laser (QCL) element having a reduced threshold current density (J) and an increased maximum operating temperature (T). [SOLUTION] One embodiment of the present invention provides a THz-QCL element () with a QCL structure (), which is a semiconductor superlattice (A) sandwiched between a pair of electrodes (). The semiconductor superlattice (A) (QCL structure ()) is provided with an active region () that emits THz range electromagnetic waves due to the transition of electrons between sub-bands during application of a voltage to the pair of electrodes, for example. The active region () has repeating unit structures (U) of a thickness, which includes sets of a well layer (W) and a barrier layer (B) alternatingly laminated with each other, wherein the well layer (W) is made of AlGaAs (where 0<x<1), which is a mixed crystal of AlAs and GaAs.