Quantum computing promises to solve some otherwise intractable problems, but there is not yet a generally accepted technology for building a quantum computer. Electrons bound to superfluid helium have been suggested as qubits, utilizing either a motional state or an electron's spin as the qubit. Our work has largely concentrated on spin qubits, which have been calculated to have exceptionally long coherence. A key anticipated advantage of these qubits is that the size scale of the quantum gates can be comparable to that of semiconductor devices, opening the possibility of monolithically integrating the entire computer on one chip. At the same time there is evidence that devices will not require individual tuning since there are no random trapped charges, as one finds in semiconductors. However, we must essentially invent a new technology for controlling these electrons. I will show data on shuttling small packets of electrons around a chip in Charge Coupled Devices (CCD), and above thin He films which we need for small devices. I will also discuss recent experiments on electron confinement in 100nm-scale quantum dots, and pushing the sensitivity of capacitive sensing to near the single-electron level.
