  Room-temperature fluorescence detection of the nitrogen-vacancy center
electronic spin typically has low signal to noise, requiring long experiments
to reveal an averaged signal. Here, we present a simple approach to analysis of
time-resolved fluorescence data that permits an improvement in measurement
precision through signal processing alone. Applying our technique to
experimental data reveals an improvement in signal to noise equivalent to a 14%
increase in photon collection efficiency. We further explore the dependence of
the signal to noise ratio on excitation power, and analyze our results using a
rate equation model. Our results provide a rubric for optimizing fluorescence
spin detection, which has direct implications for improving precision of
nitrogen-vacancy-based sensors.
