| 摘要 |
The laser has three regions p-n-n+ or n-p-p+ of magnetic element alloyed Group II-VI elements such as Cd, Hg, and Te doped with an element having a high atomic radius such as Sb or In. The magnetic element may be Mn or Fe. Vapor phase epitaxy is used to create a substrate having graded energy band gap characteristic across its thickness. A two-step liquid phase epitaxy process is used to grow an active layer and a passive layer to create the laser heterostructure. The index of refraction of the active region is higher than the indexes of refraction of the substrate and passive regions. The graded energy band gap and high doping of the substrate region results in a very low resistance which minimizes a temperature rise resulting from joule heating at high current densities. The relationship of the indexes of refraction of the layers result in double sided optical confinement to support lasing. In a semimagnetic semiconductor such as HgMnTe, the coefficient dEg/dB is large and opposite than in nonmagnetic semiconductors, making it possible to tune the laser by external magnetic fields.
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