CDSM-FS - Feasibility Study of a Coupled Dark State magnetometer

Project: Research project

Project Details


An absolute scalar magnetometer offers superior stability and
offset-free measurements of the magnetic field magnitude. In
space, it is used for improving the absolute accuracy of vector
magnetometers, which also measure the direction of the
magnetic field. In several cases, full science return can only be
achieved by a combination of vector and scalar magnetometers.
Existing scalar magnetometers are based on complex instrument
designs, which have significant mass and power consumption.
A miniaturized scalar magnetometer is therefore a key technology
for a number of future space missions (e.g. ESA's Europa Jupiter
System Mission to Jupiter's moon Ganymede).
In the frame of this project a feasibility study of a new type of
scalar magnetometer called Coupled Dark State Magnetometer
(CDSM) was carried out. It included the investigation of its
technical readiness and scientific merit for space applications,
the concept for a TRL 5 (component and/or breadboard validation
in relevant environment) compliant design, a detailed
investigation of key components as well as the identification of
possible challenges for a reliable operation in space.
The CDSM is a kind of optically pumped magnetometer. This
means that the energy from a light source (e.g. laser diode) is
used for exciting electrons in an atom in order to gain information
about the magnitude of the surrounding magnetic field. In case
of the CDSM the optical source is a specially modulated laser
light, which excites Rubidium atoms stored in a glass cell. The
measurement of the magnetic field is based on the Zeeman
Effect in free atoms. Here, the energy shift of the atomic levels
is described by the so called Breit-Rabi formula, which only
contains fundamental natural constants (such as Land factors,
Bohrs magneton and Plancks constant). Therefore, the
determination of magnetic fields is reduced to a frequency
measurement, which can be done with highest accuracy.
During the feasibility study improvements have been made to
a TRL 3 (characteristic proof of concept) compliant test set-up
for a better resource estimation of the most relevant instrument
parts. The current best estimates for mass and power are
700 g and 1.0 W, respectively. All technology and every
component are available so that there is nothing that could
prevent a further TRL uplift of the CDSM to level 5 and higher.
Effective start/end date1/06/0931/03/10