Mechanical Quantum Resonators: Quantum Optics with Phonons

机械量子谐振器：声子量子光学

• 批准号: 0605818
• 负责人: Andrew Cleland
• 金额: $ 35.5万
• 依托单位: University of California-Santa Barbara
• 依托单位国家: 美国
• 项目类别: Continuing grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-07-01 至 2011-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0605818&HistoricalAwards=false
• 关键词: Mechanical; Quantum; Resonators; Optics; Phonons

****NON-TECHNICAL ABSTRACT****:Quantum mechanics controls the behavior of very small, atomic-scale systems like the hydrogen atom and the electron. Demonstrations of the applicability of quantum mechanics to larger scale systems, especially ones with millions or more independent atoms, are challenging due to the need to isolate the system of interest from the environment that surrounds them, an environment that demolishes the quantum effects so peculiar to our classical experience. To date, no clear demonstration of quantum effects in large systems has been performed, certainly not in large mechanical systems. This project will focus on the construction of small mechanical resonators, similar to quartz crystals used to time computer circuits, sufficiently disconnected from the rest of the world to allow quantum effects to be displayed in an unambiguous fashion. In particular, the quantum nature of vibrational energy, which is predicted to change in steps rather than in a continuous fashion, will be explored in detail. The multidisciplinary project integrates research and education in order to train students and postdoctoral researchers in modern methods required to address this key problem in physics, which will be integrated with engineering and nanotechnology to achieve the goals set forward here. The acquired interdisciplinary skills, which include state-of-the-art nanofabrication and radiofrequency and microwave technology, prepare the trainees for careers in academe, national laboratories, and industry.****TECHNICAL ABSTRACT****:This project will investigate mechanical resonators in the low-temperature, single-phonon quantum regime. The study will focus on a novel type of high quality factor, GHz frequency piezoelectric resonator, which can have an unprecedented quality factor in this frequency band. The quantum mechanical properties of the resonators, especially in the single-phonon regime, will be probed by Josephson junction circuits recently developed for applications to superconducting quantum computation. A resonator coupled to one or more Josephson junctions provides a beautiful solid-state analog to cavity quantum electrodynamics, and this project will explore a variety of quantum optical phenomena with the coherent phonons. The goals of the project are to reveal values for the relaxation time and the coherence time of the resonator, allowing a first connection to the classical quality factor; to demonstrate "quantum refrigeration", removing individual phonons from a resonator with multi-phonon occupation; and to pursue squeezing effects controlled by the Josephson junction qubit. This would comprise the first demonstration of quantum mechanics in a macroscopic mechanical system, and a milestone in quantum physics. The multidisciplinary project integrates research and education in order to train students and postdoctoral researchers in modern methods required to address this key problem in physics, which will be integrated with engineering and nanotechnology to achieve the goals set forward here.

****非技术摘要****：量子力学控制非常小的原子级系统（如氢原子和电子）的行为。证明量子力学适用于更大规模的系统，特别是具有数百万或更多独立原子的系统，具有挑战性，因为需要将感兴趣的系统与其周围的环境隔离开来，而这种环境会破坏量子效应，而这些环境是量子力学所特有的。我们的经典经历。迄今为止，还没有在大型系统中进行量子效应的明确演示，尤其是在大型机械系统中。该项目将专注于建造小型机械谐振器，类似于用于对计算机电路计时的石英晶体，与世界其他部分充分隔离，以便以明确的方式显示量子效应。特别是，振动能量的量子性质预计会逐步变化，而不是连续变化，将被详细探讨。该多学科项目将研究和教育融为一体，旨在培养学生和博士后研究人员使用解决这一物理学关键问题所需的现代方法，并将其与工程和纳米技术相结合，以实现此处设定的目标。获得的跨学科技能，包括最先进的纳米制造以及射频和微波技术，为学员在学术界、国家实验室和工业界的职业生涯做好准备。****技术摘要****：该项目将调查低温、单声子量子态的机械谐振器。该研究将重点关注一种新型高品质因数、GHz 频率压电谐振器，该谐振器在此频段具有前所未有的品质因数。谐振器的量子力学特性，特别是在单声子状态下，将通过最近开发的用于超导量子计算的约瑟夫森结电路来探测。耦合到一个或多个约瑟夫森结的谐振器为腔量子电动力学提供了一种美丽的固态模拟，该项目将探索相干声子的各种量子光学现象。该项目的目标是揭示谐振器的弛豫时间和相干时间的值，从而首次连接到经典品质因数；演示“量子制冷”，从多声子占据的谐振器中去除单个声子；并追求由约瑟夫森结量子位控制的挤压效应。这将是量子力学在宏观机械系统中的首次演示，也是量子物理学的一个里程碑。该多学科项目将研究和教育融为一体，旨在培养学生和博士后研究人员使用解决这一物理学关键问题所需的现代方法，并将其与工程和纳米技术相结合，以实现此处设定的目标。