Skip to content

Geometric phase magnetometry using a solid-state spin

MetadataDetails
Publication Date2018-11-21
JournalNature Communications
AuthorsKeigo Arai, J. Lee, Chinmay Belthangady, David R. Glenn, H. Zhang
InstitutionsCenter for Astrophysics Harvard & Smithsonian, Massachusetts Institute of Technology
Citations28

Abstract A key challenge of magnetometry lies in the simultaneous optimization of magnetic field sensitivity and maximum field range. In interferometry-based magnetometry, a quantum two-level system acquires a dynamic phase in response to an applied magnetic field. However, due to the 2 π periodicity of the phase, increasing the coherent interrogation time to improve sensitivity reduces field range. Here we introduce a route towards both large magnetic field range and high sensitivity via measurements of the geometric phase acquired by a quantum two-level system. We experimentally demonstrate geometric-phase magnetometry using the electronic spin associated with the nitrogen vacancy (NV) color center in diamond. Our approach enables unwrapping of the 2 π phase ambiguity, enhancing field range by 400 times. We also find additional sensitivity improvement in the nonadiabatic regime, and study how geometric-phase decoherence depends on adiabaticity. Our results show that the geometric phase can be a versatile tool for quantum sensing applications.