AI 中文总结
研究在零点运动尺度实现纳米机械系统的非线性控制与读出，通过纳米管机械振荡器与双量子点电子两能级系统的超强耦合，实现了高机械非谐性及非线性连续读出，建立了可调谐平台。
AI 中文摘要
零点运动尺度下的非线性为纳米机械系统的控制和读出开辟了新途径，但实现它仍是巨大挑战。本文证明纳米管机械振荡器与双量子点电子两能级系统间的超强耦合能在零点运动尺度实现机械克尔（达芬）非线性。在色散 regime 中，大耦合产生 1.4%的机械非谐性，比之前工作大三个数量级，且保留最低能量态的主要机械性质。还展示了基于腔的机械运动纯二次连续读出，由双量子点对称性实现，通过栅极调谐可打破对称性引入大线性转导。这些结果建立了可调谐超强耦合平台，能在零点运动尺度实现强机械非谐性和非线性连续读出。
英文摘要
Nonlinearity at the scale of zero-point motion opens new possibilities for the control and readout of nanomechanical systems, but achieving this remains a formidable challenge. Here we demonstrate that ultrastrong coupling (USC) between a nanotube mechanical oscillator and a double-quantum-dot electronic two-level system enables a mechanical Kerr (Duffing) nonlinearity at the zero-point motion scale. In the dispersive regime, this large coupling yields a mechanical anharmonicity of $α= 1.4\%$ - three orders of magnitude larger than in previous work - while preserving the predominantly mechanical nature of the lowest energy states. We further demonstrate a purely quadratic cavity-based continuous readout of the mechanical motion. This continuous nonlinear optomechanical readout is enforced by a double-quantum dot symmetry, which can be broken by gate tuning to introduce a large linear transduction. These results establish a tunable USC platform that enables strong mechanical anharmonicity and nonlinear continuous readout at the zero-point motion scale.
