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arXiv · 2107.14788

Fine structure of current noise spectra in nanoelectromechanical resonators

Dong E. Liu·Alex Levchenko
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Abstract

We study the frequency-dependent noise of a suspended carbon nanotube quantum dot nanoelectromechanical resonator induced by electron-vibration coupling. Using a rigorous Keldysh diagrammatic technique, we establish a formal framework connecting the vibrational properties to electrical measurements. We find that the noise power spectrum exhibits a narrow resonant peak at the frequency of the vibrational modes. However, this fine structure tends to disappear due to a coherent cancellation effect when the tunneling barriers are tuned to a symmetric point. Notably, measuring the electrical current noise spectra provides a sensitive alternative method for detecting the damping and dephasing of quantum vibrational modes.

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Dong E. Liu, Alex Levchenko. 2021-07-30. Fine structure of current noise spectra in nanoelectromechanical resonators. https://doi.org/10.1063/10.0034370

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