Nitrogen-vacancy (NV) centers in mm-scale diamond samples were produced by

irradiation and subsequent annealing under varied conditions. The optical and spinrelaxation

properties of these samples were characterized using confocal

microscopy, visible and infrared absorption, and optically detected magnetic

resonance. The sample with the highest NV− concentration, approximately 16ppm

(2.8 x 1018cm−3), was prepared with no observable traces of neutrally charged

vacancy defects. The effective transverse spin-relaxation time for this sample was

118ns, predominately limited by residual paramagnetic nitrogen which was

determined to have a concentration of 49ppm. Under ideal conditions, the shotnoise

limited sensitivity was projected to be ~150fT/√Hz for a 100μm-scale

magnetometer based on this sample. Other samples with NV− concentrations from

0.007 to 12ppm and effective relaxation times ranging from 27 to over 291ns were

prepared and characterized. Diamonds with a High Density of Nitrogen-Vacancy Centers for Magnetometry

Applications. V.M.Acosta, E.Bauch, M.P.Ledbetter, C.Santori, K.M.C.Fu,

P.E.Barclay, R.G.Beausoleil, H.Linget, J.F.Roch, F.Treussart, S.Chemerisov,

W.Gawlik, D.Budker: Physical Review B, 2009, 80[11], 115202