Cubic GaN quantum dots embedded in zinc-blende AlN microdisks

Microresonators containing quantum dots find application in devices like single photon emitters for quantum information technology as well as low threshold laser devices. We demonstrate the fabrication of 60 nm thin zinc-blende AlN microdisks including cubic GaN quantum dots using dry chemical etching techniques. Scanning electron microscopy analysis reveals the morphology with smooth surfaces of the microdisks. Micro-photoluminescence measurements exhibit optically active quantum dots. Furthermore this is the first report of resonator modes in the emission spectrum of a cubic AlN microdisk.

► Fabrication of thin zinc-blende AlN microdisks with embedded cubic GaN quantum dots. ► Development of a dry chemical under-etching technique for 3C-SiC substrates. ► Scanning electron microscopy analysis reveals the morphology with smooth surfaces of the microdisks. ► Micro-photoluminescence measurements exhibit optically active cubic GaN quantum dots. ► Clearly distinguishable whispering gallery modes in the emission spectrum of cubic AlN microdisks.