标题： TWPA应用于光学机械平台的定量校准 显示英文标题

标题： Quantitative calibration of a TWPA applied to an optomechanical platform

摘要： 在过去十年中，微波量子电子学工具箱增加了诸如行波参量放大器（TWPAs）之类的量子限幅检测设备。它们提供的极高灵敏度不仅是量子信息处理中某些物理应用所必需的，也是决定量子传感设置检测极限的关键因素。在微波光机械系统框架内，可以获得前所未有的小运动和力的范围，为此需要进行特定的定量校准。我们报告了在4毫开尔文至400毫开尔文温度范围内使用铝鼓膜机械装置进行的接近量子限幅的测量。整个设置经过仔细校准，特别是考虑到超导光机械腔中微波吸收随功率变化的影响。这种影响通常归因于金属氧化物中存在的双能级系统（TLSs）。我们证明TWPA中存在类似特征，并可以用适应的表达式进行现象学拟合。研究了全参数范围内的功率和温度依赖性，从而得出了声子群体（即布朗运动幅度）的绝对定义，不确定性为±20%。 显示英文摘要

摘要： In the last decade, the microwave quantum electronics toolbox has been enriched with quantum limited detection devices such as Traveling Wave Parametric Amplifiers (TWPAs). The extreme sensitivity they provide is not only mandatory for some physics applications within quantum information processing, but is also the key element that will determine the detection limit of quantum sensing setups. In the framework of microwave optomechanical systems, an unprecedented range of small motions and forces is accessible, for which a specific quantitative calibration becomes necessary. We report on near quantum-limited measurements performed with an aluminum drumhead mechanical device within the temperature range 4 mK - 400 mK. The whole setup is carefully calibrated, especially taking into account the power-dependence of microwave absorption in the superconducting optomechanical cavity. This effect is commonly attributed to Two-Level-Systems (TLSs) present in the metal oxide. We demonstrate that a similar feature exists in the TWPA, and can be phenomenologically fit with adapted expressions. The power and temperature dependence is studied over the full parameter range, leading to an absolute definition of phonon population (i.e. Brownian motion amplitude), with an uncertainty +-20 %.