Field-able scalar magnetometers have now reached impressive sensitivities on the order of0.1pT √ Hz  with laboratory versions promising a few orders of magnitude improvement. However, at this level, practical applications at low frequencies, e.g. anti-submarine warfare (ASW), are limited by environmental noise and not fundamental sensor noise. A standard technique to circumvent this limitation is to employ two magnetometers separated by a given distance (Δz) and subtract the measurements (ΔB), resulting in a so called gradient measurement (ΔB / Δz) that can cancel out common noise. Recently, I proposed a method to measure magnetic field gradients using an atom interferometer¹. This method has the unique advantage of being an intrinsic gradiometer with a very short baseline. At the very heart of this device is an atom beam-splitter that can create super-positions of magnetic sensitive transitions using Raman pulses, in contrast with other existing atom interferometer sensors that use magnetically insensitive transitions. In this talk, I’ll discuss our work to measure Raman spectra in the presence of an arbitrary magnetic field. I’ll present the results (and pitfalls!) of our multi-level theoretical model and present the results of our recent measurements.

Location: Physics Bldg., Room 401