Diamond crystal stress imaging using nitrogen-vacancy centers in diamond

We will present our work using nitrogen-vacancy (NV) defect centers in diamond to optically image the crystal stress tensor elements of a diamond sample. Motivated by our ongoing progress using 2D layers of NV centers for magnetic microscopy in geology and biology, we will discuss how strain defects in a diamond crystal can spoil the magnetic sensitivity and give rise to false magnetic features. We will describe our technique for reconstructing the diamond stress tensor from optically-interrogated NV resonance frequencies, validate and compare with measurements from a built-in birefringence imager, catalog the types of strain features common to our synthetic diamond chips, and discuss how this work enables improved NV magnetic and stress sensing.