LATERAL VARIATION AND CONTROL OF THE REFRACTIVE INDEX AND THE TWO-DIMENSIONAL BOUND STATES IN GaAs/GaAIAs SUPERLATTICE STRUCTURES

In multiquantum-well and superlattice structures the physical properties - e.g. the energy of bound states and the refractive index - strongly depend on the superlattice periodicity. On the other side, the growth rate of the GaAs and GaAIAs is very sensitive to the crystallographical orientation. Applying these properties using nonplanar substrates multiquantum-well structures were grown, where the lattice periodicity were different in the different directions. The structures grown into GaAs grooves or onto linear mesa-structures have boundary planes along their axis where the refractive index perpendicular to the axis was lower than along the axis. This results in a strong wave-guiding making possible to develop a new type of semiconductor laserdiode