Experiments

Mitos – magnetic induction tomography with optical sensors

Magnetic Induction Tomography (MIT) is a long standing imaging technique [1] sensitive to all passive electromagnetic properties of materials. It is very appealing for many applications in the industrial, biomedical and security domains thanks to its low-cost and non-invasive properties. It is thus an exciting research topic, with potential commercial applicability.
In classical MIT experiments, an oscillating rf magnetic field is generated and the Eddy currents induced by the presence of a conductive material are detected by a sensor, typically a coil. By displacing the object relative to the sensor a map is generated. Recently, Optica Atomic Magnetometers (OAM) have been applied as sensors for MIT [2]. The extremely high sensitivity of OAMs [3], which employ typically a thermal vapor of alkali atoms, has shown capable to improving the performances of MIT sensors.
In this experiment we propose to use as MIT sensor a sample of ultra-cold Rb atoms at temperatures below 100 μK confined in an optical trap. This should improve both the spatial resolution and the sensitivity of the magnetometer thanks to the esquisite control allowed by laser cooling techniques and by the long interaction time with the radiation.

This experiment is performed, in partnership with University College London (UK), York Instruments (UK), Marwan Technologies (I) and Valis Engineering (I) within the project “Magnetic Induction Tomography with Optical Sensors – MITOS”, funded by Regione Toscana and the UE Horizon 2020 program, ERA-NET COFUND “Photonic based sensing”, acronym “PhotonicSensing” ( GA n. 688735).

[1] H. Griffiths, Meas. Sci. Technol. 12, 1126–1131 (2001)
[2] A. Wickenbrock, S. Jurgilas, A. Dow, L. Marmugi and F. Renzoni, Optics Letters 39, 6367-6370 (2014)
[3] D. Budker and M. Romalis, Nature Physics 3, 227 – 234 (2007)

Sketch of a Magnetic Induction Tomography experiment using an Optical Atomic Magnetometer

Overview of the experimental apparatus