Multiquantum barrier structure and semiconductor laser diode

摘要

A multiquantum barrier (MQB) structure includes a first superlattice layer and a second superlattice layer disposed continuously with the first superlattice layer. The first superlattice layer includes well layers having the same thickness and barrier layers having the same thickness, the well layers and barrier layers being alternatingly laminated. The second superlattice layer includes well layers having the same thickness, the well and barrier layers being alternatingly laminated. The second superlattice layer has a high electron reflectivity in an electron energy region where the electron reflectivity of the second first superlattice structure is low. Therefore, the high reflectivity of the second superlattice layer compensates for the low reflectivity of the first superlattice layer whereby a high electron reflectivity is maintained in the MQB structure.