Perspective on 2025 Nobel Prize in Physics: Macroscopic Quantum Coherence Becomes an Engineered Resource

The 2025 Nobel Prize in Physics recognizes a conceptual shift that has been more than a century in the making: the transition from observing quantum phenomena in materials to deliberately engineering quantum behaviour in macroscopic electrical circuits. Awarded to John Clarke, Michel Devoret, and John Martinis, the prize honours the experimental demonstration and control of macroscopic quantum tunnelling and energy quantization in superconducting circuits. Their work resolved a long-standing question at the heart of quantum mechanics: can an object large enough to wire, probe, and manipulate behave as a single quantum system? The answer, now unequivocally, is yes.