Optical investigation of InAs/InP(1 0 0) quantum dots grown by gas source molecular beam epitaxy

We report on the optical characteristics of InAs quantum dots based on the InP(1 0 0) substrate grown by gas source molecular beam epitaxy without assisting any other methods. The photoluminescence was carefully investigated by adjusting the thickness of InAs layers and the growth temperature. A wide range of emitting peaks is obtained with the increase in the thickness of InAs layers. In addition, we find that the morphology and shape of quantum dots also greatly depend on InAs layers. The images of atomic force microscopy show that the quantum dots like forming into quantum dashes elongated along the [0 1 −1] direction when the thickness of InAs layers increased. A critical thickness of formation quantum dots or quantum dash is obtained. At the same time, we observe that the growth temperature also has a great impact on the emission wavelength peaks. High qualities of InAs/InP(1 0 0) quantum dots providing their emission wavelength in 1.55 μm are obtained, and good performances of quantum dots lasers are fabricated.

► The InAs QD was deposited on the InP(1 0 0) substrate by GSMBE without assisting any other methods.
► A critical thickness of formation quantum dots or quantum dash is obtained.
► A suitable thickness of InAs layers is obtained with a uniform size distribution of QDs.
► A suitable growth temperature is obtained with PL peaks of 1.55 μm.