As physicists we would like to have a detailed understanding of the characteristics of the system we study. But there is not only this academic interest: we are serious about applying our technique of coherent dark state preparation to various precision measurements. This requires not only a high sensitivity but also a detailed understanding of the characteristics of the dark resonances so that systematic effects can be understood and then avoided or corrected for. An important aspect is the line shape and how it changes. We have developed a special technique to record these line shapes with high resolution.

This allows us to examine dark resonances with unprecedented resolution and accuracy: