CDSM TRL-Uplift - Uplift of the Technology Readiness Level of the Coupled Dark State Magnetometer

The aim of this project was to raise the Technology Readiness Level (TRL) of a new type of scalar magnetometer called Coupled Dark State Magnetometer (CDSM). Advantages of the CDSM are the uncomplicated sensor design, the high dynamic range of more than 6 decades and the omni-directional measurement capability without additional design complexity.

Short Description

An absolute scalar magnetometer offers superior stability and offset-free measure- ments 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.

The CDSM is a special 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. The optical source of the CDSM 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 creation of a quantum-interference effect called coherent population trapping in conjunction with 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 Landé factors, Bohr magneton and Planck’s constant). Therefore, the determination of magnetic fields is reduced to a frequency measurement which can be done with highest accuracy.

This project directly followed a feasibility study funded under ASAP 6. It included the development of a miniaturized Laboratory Model and an Engineering Model for the Chinese Electro- Magnetic Satellite (EMS) mission. It enabled a TRL of 5 (component validation in relevant environment) at the end of the project, which was required for the participation in a multi-sensor magnetometer proposal for the European Jupiter mission.

Project Partners


Austrian Academy of Sciences (ÖAW), Space Research Institute (IWF) - Werner Magnes


Graz University of Technology, Institute of Experimental Physics - Roland Lammegger

Contact Address

Austrian Academy of Sciences (ÖAW) - Space Research Institute (IWF)
Werner Magnes
Schmiedlstraße 6
A-8042 Graz
Tel.: +43 (316) 4120 - 562