Quantum sensing of magnetic fields with molecular color centers
At a Glance
Section titled āAt a Glanceā| Metadata | Details |
|---|---|
| Publication Date | 2023-11-08 |
| Journal | Physical Review Research |
| Authors | Kathleen R. Mullin, Daniel W. Laorenza, Danna E. Freedman, James M. Rondinelli |
| Institutions | Northwestern University, Massachusetts Institute of Technology |
| Citations | 19 |
Abstract
Section titled āAbstractāMolecular color centers, such as S=1 Cr(o-tolyl){4}, show promise as an adaptable platform for magnetic quantum sensing. Their intrinsically small size, i.e., 1-2 nm, enables them to sense fields at short distances and in various geometries. This feature, in conjunction with tunable optical read-out of spin information, offers the potential for molecular color centers to be a paradigm shifting materials class beyond diamond-NV centers by accessing a distance scale opaque to NVs. This capability could, for example, address ambiguity in the reported magnetic fields arising from two-dimensional magnets by allowing for a single sensing technique to be used over a wider range of distances. Yet, so far, these abilities have only been hypothesized with theoretical validation absent. We show through simulation that Cr(o-tolyl){4} can spatially resolve proximity-exchange versus direct magnetic-field effects from monolayer CrI_{3} by quantifying how these interactions impact the excited states of the molecule. At short distances, proximity exchange dominates through molecule-substrate interactions, but at further distances the molecule behaves as a typical magnetic sensor, with magnetostatic effects dominating changes to the energy of the excited state. Our models effectively demonstrate how a molecular color center could be used to measure the magnetic field of a two-dimensional magnet and the role different distance-dependent interactions contribute to the measured field.