John Clarke (physicist)

John Clarke is a British experimental physicist who spent his whole academic career at the University of California, Berkeley, where he is now Professor Emeritus. He is known for measurement devices based on superconductivity, above all superconducting quantum interference devices, or SQUIDs, which detect extremely small magnetic fields. In the 1980s he led a research team that included John M. Martinis and Michel Devoret, and their experiments on macroscopic quantum behaviour in Josephson junction circuits earned the three of them the 2025 Nobel Prize in Physics. Clarke trained at the University of Cambridge under Brian Pippard before moving to Berkeley.