Transition energy control via strain in single quantum dots embedded in micromachined air-bridge

We have fabricated a micromachined air-bridge in which InGaAs self-assembled quantum dots are embedded. Electrostatic voltage applied between the air-bridge and the substrate pulls the air-bridge down. The deformation of the bridge produces additional strain on the matrix and the dots modifying the electronic states. The modification has been detected through a photoluminescence peak shift of a single dot. The effect of the deformation on the electronic states is evaluated with the aid of theoretical calculation using a finite element method. The good agreement between calculated and experimental energy shifts demonstrates that the energy shift is due to the strain induced by the bridge deformation. Based on the result, we discuss the capability of this micromachined device with quantum dots to control the zero-dimensional electronic system and to measure small deformation and strain.