Force detection sensitivity spectrum calibration of levitated nanomechanical sensor using harmonic coulomb force

Oscillators based on levitated particles are promising for the development of ultrasensitive force detectors. The theoretical performance nanomechanical sensors is usually characterized by so-called thermal noise limit detection sensitivity, which does not exhibit spectral specificity in practical measurements. To characterize actual performance, we propose a method sensitivity calibration sensor harmonic Coulomb force. Utilizing measured transfer function, obtained spectrum from position spectrum. Although system reached $\rm\left( {4.39 \pm 0.62} \right) \times {10^{ - 20}} N/H{z^{1/2}}$ at $\rm{2.4\times10^{-6} mbar}$ with feedback cooling, away resonance was order $\rm10^{-17} N/Hz^{1/2}$ existing level. established our study applicable to evaluation any optical levitation high-sensitivity