Publications by authors named "K Herb"
Magnetic Particle Imaging (MPI) was introduced in 2005 as a promising, tracer-based medical imaging modality with the potential for high sensitivity and spatial resolution. Since then, numerous preclinical devices have been built but only a few human-scale devices, none of which targeted functional neuroimaging. In this work, we probe the challenges of scaling the technology to meet the needs of human functional neuroimaging with sufficient sensitivity for detecting the hemodynamic changes following brain activation with a spatio-temporal resolution comparable to current functional Magnetic Resonance Imaging (fMRI) approaches.
View Article and Find Full Text PDFQuantum sensors capitalize on advanced control sequences for maximizing sensitivity and precision. However, protocols are not usually optimized for temporal resolution. Here, we establish the limits for time-resolved sensing of dynamical signals using qubit probes.
View Article and Find Full Text PDFShallow nitrogen-vacancy (NV) centers in diamond offer opportunities to study photochemical reactions, including photogeneration of radical pairs, at the single-molecule regime. A prerequisite is a detailed understanding of charge and spin dynamics of NVs exposed to the short-wavelength light required to excite chemical species. Here, we investigate the charge and spin dynamics of shallow NVs under 445 and 375 nm illumination.
View Article and Find Full Text PDFArticle Synopsis
- Optically active spin defects, like nitrogen-vacancy centers, are useful for studying nuclear spin clusters due to their high sensitivity and ability to provide atomic-scale insights.
- The research introduces advanced Fourier spectroscopy techniques to enhance the mapping and localization of carbon-13 nuclear spins around these defects at room temperature.
- The study showcases two applications of multidimensional NMR: improved localization of nuclear spins by separating hyperfine components and editing spectral data of nuclear-spin pairs to measure internuclear coupling constants, thus offering new methods for analyzing molecular structures.
Article Synopsis
- * Researchers enhance the SNR by coupling individual NVs to specially designed diamond nanopillars, which improve the efficiency of fluorescence collection.
- * The study confirms that taller nanopillars with tapered sides significantly boost SNR, making the devices easier to use with simpler optical equipment, ultimately enhancing measurement precision for scanning applications.