Quantum non-Gaussian states of phononic systems coupled to light are essential for fundamental studies of single-phonon mechanics and direct applications in quantum technology. Although nonclassical mechanical states have already been demonstrated, the more challenging quantum non-Gaussianity of such states remains limited. Using photon counting detection, we propose the quantum non-Gaussian generation of few-phonon states of low-temperature vibrating superfluid Helium. We predict the quantum non-Gaussian depth of such phononic states and investigate their robustness under relevant mechanical heating. As the quality of such phononic states is very high, we confirm a single-phonon bunching capability to further classify such states for future mechanical experiments. Moreover, we predict increasing capability for force sensing and thermometry for increasing heralded phonon numbers.

中文翻译：

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超流体氦振动的量子非高斯态


与光耦合的声子系统的量子非高斯态对于单声子力学的基础研究和量子技术的直接应用至关重要。尽管已经证明了非经典力学态，但这种态中更具挑战性的量子非高斯性仍然有限。利用光子计数检测，我们提出了低温振动超流体氦的量子非高斯产生少数声子态。我们预测了这种声子态的量子非高斯深度，并研究了它们在相关机械加热下的鲁棒性。由于这种声子状态的质量非常高，我们确认了单声子束簇能力，以进一步分类这些状态以用于未来的力学实验。此外，我们预测力传感和测温的能力将不断提高，以增加预示的声子数量。