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arXiv · 1311.2266

Room-temperature ultra-sensitive mass spectrometer via dynamic decoupling

Abstract

We propose an ultra-sensitive mass spectrometer based on a coupled quantum-bit-oscillator system. Under dynamical decoupling control of the quantum bit (qubit), the qubit coherence exhibits a comb structure in time domain. The time-comb structure enables high precision measurement of oscillator frequency, which can be used as an ultra-sensitive mass spectrometer. Surprisingly, in ideal case, the sensitivity of the proposed mass spectrometer, which scales with the temperature $T$ as $T^{-1/2}$, has better performance in higher temperature. While taking into account qubit and oscillator decay, we show that the optimal sensitivity is independent on environmental temperature $T$. With present technology on solid state spin qubit and high-quality optomechanical system, our proposal is feasible to realize an ultra-sensitive mass spectrometer in room temperature.

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Nan Zhao, Zhang-qi Yin. 2013-11-10. Room-temperature ultra-sensitive mass spectrometer via dynamic decoupling. https://doi.org/10.1103/physreva.90.042118

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