Talk Information 10/23/2025

Abstract: Precise measurements underpin scientific and technological advancements. Quantum mechanics provides an avenue to enhance precision, but it comes with a restriction: Incompatible observables, such as position and momentum, cannot be simultaneously measured to arbitrary accuracy as decreed by Heisenberg’s uncertainty principle. This restriction can be bypassed by instead measuring commuting modular observables, which are counterparts to the naturally incompatible observables. Here, we measure modular observables to estimate small changes in position and momentum with a single-mode multiparameter sensor. We deterministically prepare grid states in the mechanical motion of a trapped ion and demonstrate uncertainties in position and momentum below the standard quantum limit (SQL). Further, we examine another pair of incompatible observables—number and phase. We prepare a different resource—number-phase states—and demonstrate a metrological gain over the SQL. These results introduce previously unidentified measurement capabilities unavailable to classical systems and mark a substantial step in quantum metrology.

https://www.science.org/doi/10.1126/sciadv.adw9757

Bio: Dr. Zixin Huang obtained her PhD in quantum photonics at the University of Sydney, before moving to the University of Sheffield (UK) for a postdoctoral position as part of the Quantum Communications Hub. She was a Sydney Quantum Academy Fellow and DECRA Fellow at Macquarie University; she is currently a DECRA Fellow and RMIT VC Senior Research Fellow; her research explores quantum sensing, imaging, and how astronomers can utilise enhanced quantum imaging to probe deeper into space with unprecedented resolution.