Physics (Internal)

New applications of magnetometry based on nitrogen-vacancy centers in diamond

This event is part of the Biophysics/Condensed Matter Seminar Series.

The negatively-charged nitrogen-vacancy (NV) center in diamond is a point defect in the diamond crystal lattice which can for example be utilized as nanoscale sensor for magnetic and electric fields, strain and temperature. In my talk, I will focus on the implementation of NV centers as magnetic field sensors and two specific applications. The first application aims to perform nuclear-magnetic-resonance spectroscopy of single molecules in the regime of zero-to-ultra-low fields (i.e. larmor frequency is smaller than the molecule specific J-coupling frequency), by using a single shallow NV center. In this context, as a first step, we already developed a scheme for magnetometry using NV centers in the ZULF regime. For the second application, we use a shallow-layer NV-center ensemble in a widefield configuration to study high-Tc superconductors. Here, we already demonstrated the ability to image vortices in an yttrium-barium-copper oxide (YBCO) thin film and are focussing now on the search and investigation of superconducting islands in an underdoped YBCO film. Those superconducting islands are suggested to appear at elevated temperatures as compared to the bulk critical temperature, where the resistance of the overall resistance of the superconductor drops to zero.