Quantum superpositions and decoherence of nanomechanical rotors

基于光学悬浮各向异性粒子的操纵和控制的最新进展，我们的目标是开发创建纳米机械转子的定向量子叠加的策略。我们结合和优化了不同的方法来有效地将刚体的取向激光冷却到量子区域，并在现实环境中确定了冷却极限。除此之外，我们提出了可在实验上实现的干涉方案，从而为首次观察到纳米颗粒的定向叠加铺平了道路。最后，通过推导旋转扩散、耗散和热化的量子主方程，我们提供了精确测量扭矩和单粒子热力学基础研究所需的工具。

Based on recent progress in the manipulation and control of optically levitated anisotropic particles, we aim at developing strategies for creating orientational quantum superpositions of nanomechanical rotors. We combine and optimize different methods to efficiently laser cool the orientation of a rigid body into the quantum regime, and we identify the cooling limits in presence of realistic environments. Beyond that, we propose experimentally realizable interference protocols, thus paving the way towards the first observation of orientational superpositions of nanoparticles. Finally, by deriving the quantum master equation of rotational diffusion, dissipation, and thermalization we provide the tools required for precision measurements of torques and for fundamental studies of single-particle thermodynamics.