On April 1 2019,the Fraunhofer-Gesellschaft launches the lighthouse project"Quantum Magnetometry"(QMag):Freiburg's Fraunhofer institutes IAF,IPM and IWM want to transfer quantum magnetometry from the field of university research to industrial applications.In close cooperation with three further Fraunhofer institutes(IMM,IISB and CAP),the research team develops highly integrated imaging quantum magnetometers with highest spatial resolution and sensitivity.

　　The lighthouse project QMag enables the use of single electrons to detect smallest magnetic fields.This allows to use magnetometers in industry,for example for defect analysis of nanoelectronic circuits,for the detection of hidden material fissures or to realize especially compact magnetic resonance imaging scanners(MRI)."Our lighthouse projects set important strategic priorities to develop concrete technological solutions for Germany as an economic location.QMag paves the way for a Fraunhofer lighthouse in the field of quantum technology.The ambition of the excellent scientists who take part in the project is to significantly improve the technology and to define it internationally.In this way a long-term transfer of the revolutionary innovations of quantum magnetometry to industrial applications can be achieved",explains Fraunhofer President Prof.Reimund Neugebauer.

　　Nanoscaled magnetometry based on NV centers

　　A scanning probe magnetometer is able to measure magnetic fields with highest spatial resolution at room temperature.The magnetometer consists of single atomic vacancy complexes in diamond crystals which function as the smallest possible magnet.A nitrogen vacancy center("NV center")in diamond plays the central part.An NV center develops when two neighboring carbon atoms are removed and one is replaced with a nitrogen atom.The resulting vacancy is then occupied by the spare electron of the nitrogen atom.This electron possesses a magnetic momentum,which,after being oriented,can be used as a magnet for the magnetic field that is to be measured.Within Qmag,an NV center will be placed in the nanoscaled tip of a diamond measuring head.When this sensor tip is being moved across a sample within a scanning probe microscope,local magnetic fields can be measured with extremely high spatial resolution.In this manner the electricity distribution in nanoelectronic circuits can be made visible,considering that even the smallest electronic current produces a magnetic field that can be visualized using the quantum magnetometer.

　　"Our aim is to develop quantum magnetometers with exceptional sensory characteristics,compactness and mode of operation,which allow innovative industrial applications,and furthermore simplify the evolution of complex electronic systems in the future",says Prof.Dr.Oliver Ambacher,project manager and director of Fraunhofer IAF.

　　Diamond,as one of the most special materials in natural world,is featured with the highest hardness,low friction coefficient,high elasticity modulus,high thermal conductivity,high insulation class,wide energy gap,great sound propagation rate and favorable chemical stability,which are presented in below Table.In spite of such unique features,the natural diamond has always been existed in the form of gem,with its variability and rareness sharply limiting its application.Luoyang Yuxin Diamond Co.,Ltd‘s CVD Diamond film,on the other hand,integrates such physical and chemical properties,with lower cost than natural diamond and applicable to be made into various shapes,thus enjoying extensive application prospect in electronic industry,optical field and mechanical industry.