| 摘要 |
<p>A resonant quantum well laser (20) incorporates semiconductor barriers (26) on one or both sides of the quantum well (22) to increase the charge density within the quantum well. The composition of the injection layers (24) can be tailored in a manner that the energies of the charge carriers in the injection layers are about that of a resonant energy level for that type of charge carrier in the quantum well. The barrier layers (26) on one or both sides of the quantum well (22) enhance the probability of the charge carrier being in the well for a longer time and travelling a longer distance, increasing the chance of scattering. The charge carriers, electrons or holes, can move from their respective injection layers (24) into nearly identical energy levels within the quantum well (22), by tunneling through the thin barrier layers (26). The number of carriers which are available to transfer into the lasing energy level is increased, thereby increasing the efficiency of the laser and lowering its threshold current.</p> |
