Optimizing Pulsed Optically Detected Magnetic Resonance Acquisition: A Digital Signal Processing Perspective

Ensembles of nitrogen vacancy (NV) defect centers in diamond have attracted considerable interest for fundamental studies and applications in quantum sensing and quantum information processing. Pulsed optically detected magnetic resonance (ODMR) and related pulse-sequence protocols are essential for the coherent manipulation and characterization of the NV spins. Here, we introduce a novel framework for analyzing pulsed ODMR data acquisition and subsequent processing from the perspective of digital signal processing (DSP). As a central part of this approach, we model the data processing procedure as an effective digital bandpass filter that suppresses a broad range of noise spectral components, thereby reducing the noise in the processed data. This analysis identifies an intermediate frequency (IF) band whose spectral contribution to this noise is maximum. The proposed DSP-based analysis is experimentally validated using an oscilloscope based acquisition method, and is also applied to optimize key measurement parameters. In particular, the introduction of an analog low pass filter in the signal path is shown to remove aliasing of noise into the IF band, and thus improve signal quality. Our results also establish the oscilloscope as a viable data acquisition device for pulsed ODMR, with practical advantages including on-board waveform averaging, real-time signal visualization, and simplified system debugging. The proposed framework can be extended to other detection techniques and material platforms for ODMR.