Electrically tunable electron g factors in coupled InAs/GaAs pyramid quantum dots

摘要

The electron g factors of coupled InAs/GaAs quantum dots under external magnetic and electric fields are investigated by using the eight-band k·p model. The resonant coupling between the two dots remains under electric fields below 8.2 mVm, and is broken above the critical field due to the quantum Stark effect. By applying electric fields, a sign reverse of g factors is observed, and an electric field tunable zero g factor is found in the quantum dot molecules. Spin-orbit interactions nicely explain the transition mechanism of g factors under external electric fields.