EXPLORING THE MECHANISM OF ABNORMAL RESONANCE SIGNALS IN OPTICAL PUMPING MAGNETIC RESONANCE EXPERIMENT USING DIGITAL OSCILLOSCOPE

The abnormal resonance signals in optical pumping magnetic resonance experiment were determined according to the value of g_F-factor obtained by fitting. The spectra of the abnormal resonance radio-frequency signals were measured using digital oscilloscope, and the magnitudes of the higher harmonics were calculated. The relationship between the amplitudes of normal resonance signals and the ones of radio-frequency signals was obtained by the least squares linear fitting. Using the relationship, the magnitude of the abnormal resonance signal engendered by each higher harmonic was estimated. The calculated results are basically consistent with the experimental ones. The waveforms and the spectra of the radio-frequency signals change obviously after the frequency meter is connected with the radio-frequency signal generator. The abnormal resonance signals change accordingly with the changes in the RF signal spectrum, which suggests that the abnormal resonance signals are caused by the higher harmonic resonances of the radio-frequency signals. These results show that it is not only feasible to explore the mechanism of abnormal resonance signal in optical magnetic resonance experiment by digital oscilloscope, but can also quantitatively estimate and predict the influence of radio-frequency signal waveform on the magnitude of abnormal resonance signals.