Spectroscopy of Single AlInAs and (111)-Oriented InGaAs Quantum Dots

A system of AlInAs- and InGaAs(111)-based quantum dots is studied. The use of wide-gap Al_xIn_1–xAs alloys as a basis for quantum dots provides a means for substantially extending the spectral region of emission to shorter wavelengths, including the region close to 770 nm which is of interest for the engineering of aerospace systems of quantum cryptography. The fine structure of exciton states in AlInAs and InGaAs(111) quantum dots is studied. It is shown that, for a set of quantum dots, the splitting of exciton states is comparable to the natural width of exciton lines, which is of interest for the engineering of emitters of photon pairs on the basis of these quantum dots.