Jonathan Williams joined NPL in 1983 with a degree in Physics from Oxford University and later was awarded a PhD from City University for his work on electrical quantum standards. He has developed a number of cryogenic current comparator systems including resistance ratio bridges for the quantised Hall effect as well as resistance standards operating at currents from 100 A to 100 nA. He also introduced the direct synthesis of voltage waveforms in terms of the Josephson effect to NPL and established a range of measurement systems and techniques. More recently he has been engaged in research relating to superconducting nano-devices for Josephson effect and parametric amplification.
Jonathan is a Fellow of the Institution of Engineering and Technology, a Chartered Engineer and a Liveryman of the Worshipful Company of Scientific Instrument Makers. In 2011, he was awarded the Callendar Medal for his work on quantum electrical standards and the SI.
Areas of interest
Jonathan’s research interests are centred on the application of superconductivity and the Josephson effect to quantum electrical metrology, also the development of amplifiers and sensors operating at the quantum limit. Activities include:
- Development of primary standards of voltage and resistance for routine use in calibration and industrial environments
- Development of next-generation Josephson standards for waveform metrology
- Design of low noise instrumentation for observation of quantum effects in sensors and systems
- Design, modelling and measurement of superconducting nano-devices and their application to parametric amplifiers and superconducting circuits