Fig. 2: Working principles of diamond NV center-based receiver.
From: Towards ubiquitous radio access using nanodiamond based quantum receivers
a NV center-based RF signal detection: Converting amplitude or frequency modulated microwaves into fluorescence intensities. b Amplitude demodulation illustrates optically detected magnetic resonance (ODMR) near 2.87 GHz with transmission powers P1 < P2. c Frequency demodulation places the carrier frequency on the slope, mapping frequency changes onto fluorescence intensities. d Joint demodulation shows four unique combinations of frequencies and power levels. e Amplitude modulation reveals an inverse relationship between fluorescence intensity and microwave power. f Frequency modulation demonstrates a direct correlation between fluorescence intensity and microwave frequency. g Results of 30 experimental repeats. Joint amplitude-and-frequency modulation presents four distinct fluorescence intensity states. h–j Comparison of demodulated fluorescence intensities with expected audio signals, accompanied by respective residuals in histograms, for (h) amplitude, (i) frequency, and (j) joint modulations.
