Conclusion

SQUID encoders have demonstrated exceptional performance thanks to the unique properties of the superconducting state: flux quantization, very short response times and low dissipation. In particular, their resolution and speed have already surpassed all other achievements; the existence of the flux quantum makes it possible to envisage circuits with very high linearity and dynamics. This would not have been possible without cooling the circuits, which are limited by thermal noise (for ADCs with 14 bits or more), or by gate time (ADCs with less than 14 bits). The improvement in semiconductor ADCs is one and a half bits over 8 years, which by extrapolation would give superconducting technology a 15-year lead.

The introduction of high-temperature superconducting technology would make it possible to work at temperatures of the order of 30 K, with an error rate compatible...