Measuring magnetic fields with magnetic field insensitive transitions

Abstract

Magnetometry is an important tool prevalent in many applications such as fundamental research, material characterization and biological imaging. Atomic magnetometry conventionally makes use of two quantum states, the energy difference of which depends linearly on the magnetic field due to the Zeeman effect. The magnetic field is evaluated from repeated measurements of the accumulated dynamic phase between the two Zeeman states in a superposition. Here we propose a magnetometry method that employs a superposition of clock states with energies that do not depend, to first-order, on the magnetic field magnitude. Our method makes use of the geometrical dependence of the clock-states wavefunctions on the magnetic field orientation. We propose detailed schemes for measuring both static and time-varying magnetic fields, and analyze the sensitivity of these methods. We show that, similarly to Zeeman-based methods, the smallest measurable signal scales inversely with the system coherence-time, which for clock transitions is typically significantly longer than for magnetically sensitive transitions. Finally, we experimentally demonstrate our method on an ensemble of optically trapped 87Rb atoms.

arXiv comment10+5 pages, 4+5 figures

References in corpus (13)

• Quantum sensing
• Optical Magnetometry
• Long-lived qubit memory using atomic ions
• Sub-femtotesla scalar atomic magnetometer using multipass cells
• Single Ion Quantum Lock-In Amplifier
• Improved Limits on Spin-Mass Interactions
• Test of Lorentz invariance with spin precession of ultracold neutrons
• Cs CPT magnetometer for cardio-signal detection in unshielded environment
• Single-Spin Spectrum-Analyzer for a Strongly Coupled Environment
• Extended coherence time on the clock transition of optically trapped Rubidium
• Observation of Topological and Parity-dependent Phase of $m=0$ Spin States
• Measurement of the spin-dipolar part of the tensor polarizability of ${}^{87}$Rb
• Rabi oscillation induced $\pi$-phase flip in an unbalanced Ramsey atom interferometer