Quantum Sensing

Quantum Imaging of Living Tissues with Magnetic Nanoparticles

Developing an understanding of the underlying processes of cancer dissemination is to this day a pressing topic in medical and biological research. Behavior of individual cells inside living tissue can not be accurately observed in real time without interfering with the sample. Subsequently a fundamental aspect of the biological processes involved in the developement of metastasis remains uncertain, due to the lack of resolution and sensitivity of available imaging techniques. As such, widefield imaging with ensembles of  nitrogen-vacancy centers (NV-Centers) in diamond as a quantum sensor offers outstanding properties, allowing the observation of individual cells through magnetic field vector mapping by selectively attaching superparamagnetic iron oxide nanoparticles (SPIONs) to the cells of interest. Stimulating these particles via application of a magnetic bias field results in a magnetic dipole emitted by the superparamagnetic properties of said particles, which adds onto the known bias field. This total magnetic field vector causes a lift of the degeneracy of the NV-Centers spin states. Evaluating the spin transitions via optically detected magnetic resonance (ODMR) and knowledge of the applied bias field enables the reconstruction of the full magnetic field vector. This enables the single cell tracking in living organic tissue inside the incubator of a homemade integrated widefield microscope over the span of multiple days in close to real time.

Quantum sensing of liquid electrolytes with NV-centers in nanodiamonds

To use batteries as large-scale energy storage systems it is necessary to measure and understand their degradation in-situ and in-operando. As a battery’s degradation is often the result of molecular
processes inside the electrolyte, a sensing platform which allows to measure the ions with a high spatial resolution is needed. Primary candidates for such a platform are NV-centers in diamonds. Within this project we want to use nanodiamonds with NV-centers to sense the electric field generated by the ions in the electrolyte and therefore to measure and understand the degradation of batteries.