Fig. 2: Magnetic microscopy.
From: Magnetic microscopy for operando imaging of battery dynamics
a–c Measurement modalities of scanning nitrogen vacancy (NV) magnetometry where the NV sensor is scanned with respect to the sample surface to acquire an image of the magnetic stray field. The stray field is used to infer knowledge about magnetic order, magnetic susceptibility, and current distributions. d Simplified electronic structure of the NV where non-radiative processes lead to lower fluorescence intensity of the ms = ±1 states and to a polarization into the ms = 0 spin state. e Schematics of the fluorescence intensity as a function of microwave frequency. When the frequency is resonant with the ms = 0 to ±1 transition, two dips with reduced fluorescence split by the Zeeman effect enable the detection of magnetic fields. f Schematics of various magnetic field sources in batteries, which can be measured with scanning NV magnetometry, including magnetization at the positive & negative electrodes and ionic & electronic current distributions.
