Semiconductor laser device

摘要

A semiconductor laser device having an active layer, a pair of cladding layers interposing the active layer and a multi-quantum barrier provided between one of the pair of cladding layers and the active layer is provided. The multi-quantum barrier includes barrier layers and well layers being alternated with each other. Thickness, energy band gap, or impurity concentration of at least one of the barrier layers and well layers in the multi-quantum barrier changes with the distance from the active layer, thereby providing a stable function of reflecting carriers overflowing from the active layer back to the active layer.