Extremely efficient clocked electron transfer on superfluid helium
  Unprecedented transport efficiency is demonstrated for electrons on the surface of micron-scale superfluid helium filled channels by co-opting silicon processing technology to construct the equivalent of a charge-coupled device (CCD). Strong fringing fields lead to undetectably rare transfer failures after over a billion cycles in two dimensions. This extremely efficient transport is measured in 120 channels simultaneously with packets of up to 20 electrons, and down to singly occupied pixels. These results point the way towards the large scale transport of either computational qubits or electron spin qubits used for communications in a hybrid qubit system. 
F. R. Bradbury, Maika Takita, T. M. Gurrieri, K. J. Wilkel, Kevin Eng,   M. S. Carroll, and S. A. Lyon
cond-mat.other