Figure 2.
(a) ODMR spectrum measured in a static uniform dc magnetic field under continuous microwave excitation. The inset that shows the ODMR spectrum measured under low excitation power reveals triplet hyperfine structure due to coupling to the nitrogen nuclear spin. (b) Spin-dependent fluorescence as a function of the microwave pulse duration shows Rabi oscillations when the microwave field is resonant with a particular spin transition. (c) Ramsey fringes reveal a T2* of 1.7 μs. The red line is a fit using three exponentially decaying sine waves with frequencies given by the detuning for each of the hyperfine states. (d) A Hahn echo sequence reveals a T2 of 150 μs. The echo signal collapses and is revived at the frequency of the Larmor precession of nearby 13C nuclear spins.