Study of the limitations of the quantized acoustic current technique at PTB and NPL

We present a detailed study of surface acoustic wave devices produced at Physikalisch-Technische Bundesanstalt and Cambridge University. From the temperature dependence of the acoustic current, information on a number of critical device parameters such as the intrinsic electron temperature and Coulomb charging energy can be deduced. The results of this study indicate that the theory and experiment are in agreement and that the accuracy of the quantized acoustic current is fundamentally limited at low temperatures.