Embedded high-quality ternary GaAs1-xSbx quantum dots in GaAs nanowires by molecular-beam epitaxyOACSTPCDEI

Semiconductor quantum dots are promising candidates for preparing high-performance single photon sources.A basic requirement for this application is realizing the controlled growth of high-quality semiconductor quantum dots.Here,we report the growth of embedded GaAs1-xSbx quantum dots in GaAs nanowires by molecular-beam epitaxy.It is found that the size of the GaAs1-xSbx quantum dot can be well-defined by the GaAs nanowire.Energy dispersive spectroscopy analyses show that the antimony content x can be up to 0.36 by tuning the growth temperature.All GaAs1-xSbx quantum dots exhibit a pure zinc-blende phase.In addition,we have developed a new technology to grow GaAs passivation layers on the sidewalls of the GaAs1-xSbx quantum dots.Different from the traditional growth process of the passivation layer,GaAs passivation layers can be grown simultaneously with the growth of the embedded GaAs1-xSbx quantum dots.The spontaneous GaAs passivation layer shows a pure zinc-blende phase due to the strict epitaxial relationship between the quantum dot and the passivation layer.The successful fabrication of embedded high-quality GaAs1-xSbx quantum dots lays the foundation for the realization of GaAs1-xSbx-based single photon sources.