Confining Single Electrons on Helium in Lithographically Defined Quantum Dots

The decoherence-free nature of the spin of an electron floating on liquid helium makes it an attractive candidate for quantum information processing. However, the precursor to measuring and controlling a spin qubit with high precision is the reliable confinement and manipulation of the electron charge state. Previous demonstrations in confinement have been successful in adding electrons and detecting single transitions in quantum dots on the order of 1-5 mm, over an order of magnitude larger than a single electron wavefunction making the realization of two-qubit exchange gates untenable. With this in mind, we fabricate arrays of highly uniform, sub-micron quantum dots that can consistently confine single electrons with a measurement accuracy of 5%.