CAREER: Probing Quantum Behavior in Qubit-Coupled Nanomechanical Systems

** 非技术摘要 ** 量子力学的发展是为了解释在不可分辨的小尺度上的现象-原子和基本粒子的领域。 然而，值得注意的是，它已经在一个实验领域进行了测试，没有失败，现在从物质的组成扩展到广泛的工程设备。 这就引出了一个重要的基本问题：量子世界和经典世界之间的边界是什么？ 这个教师早期职业发展（CAREER）项目将使用最先进的纳米尺度结构在量子和经典世界的边界进行实验研究。 实验将使用低温测量技术来引出和观察通常被经典效应掩盖的纳米级结构的脆弱量子特性。测量的成功实施将使量子系统如何“过渡”到经典状态的理论得到检验。 此外，该项目将支持在尖端纳米纤维、低温和敏感测量技术方面培训一名博士后和一名研究生。它将在包括超导设备和量子测量在内的广泛的当代物理研究课题中进行教育，并将通过拟议的合作促进国际学生交流。 这项研究还将纳入本科量子力学课程和教程，以提高学生对量子世界及其在现代技术中的作用的理解。技术摘要 ** 本学院早期职业发展（CAREER）项目的实验旨在研究量子体系中耦合纳米机械结构的动力学。 该项目将涉及超导量子位的集成，以调解纳米机械元件的弯曲模式之间的分束器类型的相互作用。 这种相互作用将在一系列测量中探索，使用低损耗超导微波谐振器分散探测联合系统的量子态。 量子位的光谱将被执行，以观察耦合设备的杂交;量子位的时域操纵将被用于产生量子位和耦合纳米机械谐振器的本征模之间的纠缠。 该项目的成功实施将使纳米机械系统中的退相干研究成为可能，并将与量子计算和测量界普遍相关。该项目将支持在纳米纤维，低温和微波测量技术的博士后和研究生的培训，它将在广泛的当代物理研究课题，包括超导设备和量子测量教育。这项研究还将被纳入本科量子力学课程和教程，以提高学生对量子世界及其在现代技术中的作用的理解。

**Non-Technical Abstract**Quantum mechanics was developed to account for phenomena at unimaginably small scales - the realm of atoms and fundamental particles. Yet, remarkably, it has been tested without failure in an experimental domain that now extends from the constituents of matter to a wide range of engineered devices. This begs an important fundamental question: What is the nature of the boundary between the quantum and classical worlds? This Faculty Early Career Development (CAREER) project will pursue experimental studies at the boundary of the quantum and classical worlds using state-of-the-art nano-scale structures. Experiments will be performed using cryogenic measurement techniques to elicit and observe fragile quantum properties of the nanoscale structures which are typically masked by classical effects. Successful implementation of the measurements will enable tests of theories about how quantum systems "transition" to the classical regime. Moreover, the project will support the training of a postdoc and a graduate student in cutting-edge nanofabrication, cryogenics and sensitive measurement techniques. It will educate both in a broad range of contemporary physics research topics including superconducting devices and quantum measurement, and will foster international student exchange through the proposed collaboration. The research will also be incorporated into an undergraduate quantum mechanics course and tutorials geared to enhance students' understanding of the quantum world and its role in modern technology.**Technical Abstract**The experiments in this Faculty Early Career Development (CAREER) project aim to study the dynamics of coupled nanomechanical structures in the quantum regime. The project will involve the integration of a superconducting qubit to mediate a beam-splitter-type interaction between flexural modes of the nanomechanical elements. This interaction will be explored in a series of measurements using a low-loss superconducting microwave resonator to dispersively probe the quantum state of the joint system. Spectroscopy of the qubit will be performed to observe the hybridization of the coupled devices; and time-domain manipulations of the qubit will be used to generate entanglement between the qubit and the eigenmodes of the coupled nanomechanical resonators. Successful implementation of the project will enable studies of decoherence in nanomechanical systems and will be of general relevance to the quantum computing and measurement communities. The project will support the training of a postdoc and a graduate student in nanofabrication, cryogenic and microwave measurement techniques, and it will educate both in a broad range of contemporary physics research topics including superconducting devices and quantum measurement. The research will also be incorporated into an undergraduate quantum mechanics course and tutorials geared to enhance students' understanding of the quantum world and its role in modern technology.