| 摘要 |
PROBLEM TO BE SOLVED: To utilize a quantum cascade(QC) laser having a simple structure for giving large freedom on the design of a QC type laser to the designer of a device. SOLUTION: A disclosed unipolar QC laser has an adjacent active region isolated by a super-lattice carrier injection/reduction region 11, and contains a multiple substantially quite the same active region. A specified active region 10 comprises a single quantum well 13 having at least two electronic states. The emission of laser beams is acquired without the population inversion of total internal sub-hands. The presence of a local population inversion is considered in response to electronic energy within the range of approximately optical phonon-energy (-35meV) from the bottom of low sub-bands in a small region in a (k) space in the vicinity of k=0 in place of the emission of laser beams. The semiconductor laser is used for substantially improving even the heat characteristics of any QC laser. |
