Tunable few-electron quantum dots in InAs nanowires

Quantum dots realized in InAs are versatile systems to study the effect of spin–orbit interaction on the spin coherence, as well as the possibility to manipulate single spins using an electric field. We present transport measurements on quantum dots realized in InAs nanowires. Lithographically defined top gates are used to locally deplete the nanowire and to form tunnelling barriers. By using three gates, we can form either single quantum dots, or two quantum dots in series along the nanowire. Measurements of the stability diagrams for both cases show that this method is suitable for producing high quality quantum dots in InAs.