Series-triple quantum dots fabricated under each control gate by the use of thermal oxidation

Triple quantum dots (QDs) connected in series were successfully fabricated by the use of pattern-dependent oxidation (PADOX) [1] of a Si nanowire and additional oxidation through the gap of three fine gate electrodes attached on the Si nanowire. This method made a QD just under each gate. The fabricated devices were confirmed that they actually consisted of three dots by the electrical measurements, in which gate capacitances between the gates and dots were successfully evaluated. These results demonstrated the applicability of PADOX method to make many QDs connected in series by increasing the number of fine gate electrodes attaching on the nanowire.