Diamond-based magnetometry utilizes the negatively charged nitrogen-vacancy color center NV. For sensing nano-scale magnetic field sources, the small size of the NV is a great advantage over other magnetometers. However, conventional implantation and growth techniques fail to produce very shallow NVs which can be brought to close proximity of small magnetic field sources. Here, we investigate innovative implantation and growth techniques to address this problem. For bulk diamond, we were able to create a concentrated layer of NVs approximately 2nm for the diamond surface. Direct measurement of magnetic sensitivity for this layer yields a sensitivity of 125nT um3/2/? Hz. For currents running in nano-scale wires on the diamond surface this translates to sensitivities below fA/? Hz. To produce superior nanodiamond magnetic sensor, we attempt growth of fluorescent nanodiamonds using two methods, High-Pressure-High-Temperature (HPHT), and plasma enhanced chemical vapor deposition CVD. We show results for fluorescent nanodiamond grown around 1-adamantylamine seed molecule. We show that the nitrogen in the seed molecule was successfully transformed to NV through electron irradiation at high temperature. Also, we show results of fluorescent nanodiamonds grown using a home built plasma CVD system. Nitrogen was introduced to the diamond by adding trimethylamine to the reactor chamber. Once again, the diamond was not fluorescent until after electron irradiation at high temperature.
