标题： 用于超流氦实验的低温腔设置，带有光纤和电气接入 显示英文标题

标题： A cryogenic chamber setup for superfluid helium experiments with optical fiber and electrical access

摘要： 超流体氦是一种典型的量子液体。 因此，它一直是研究量子多体物理的重要平台。 最近，超流体氦出色的机械和光学特性，如低机械耗散和低光学吸收，使超流体氦在从暗物质和引力波探测到量子计算的应用中成为一种有前景的材料平台。 然而，进行超流体氦实验的门槛较高，因为它们需要在密闭的低温腔体内集成复杂的光学和电气装置来限制超流体。 在此，我们报告了一种用于在毫开尔文温度下在稀释冰箱内操作的氦气腔室装置的设计和构建，该装置具有电气和光纤访问功能。 通过集成自动气体处理系统，我们可以精确控制注入腔室的氦气量，使我们的装置特别适用于超流体氦薄膜实验，例如超流体薄膜光机械学实验。 使用硅纳米光子谐振器，我们展示了对超流体氦薄膜厚度在亚纳米级别的精确控制和原位调节。 通过利用超流体薄膜厚度的优异可调性，我们在超流体薄膜中演示了光机械诱导的声子晶体腔第三声模式的声子激光，并表明激光阈值关键取决于薄膜厚度。 我们腔室的大内部体积（V_chamber = 1升）可适应各种光学和电气测量与控制技术的集成。 因此，我们的装置为基本和应用超流体氦研究中的各种实验提供了一个多功能平台。 显示英文摘要

摘要： Superfluid helium is a prototypical quantum liquid. As such, it has been a prominent platform for the study of quantum many body physics. More recently, the outstanding mechanical and optical properties of superfluid helium, such as low mechanical dissipation and low optical absorption, have positioned superfluid helium as a promising material platform in applications ranging from dark matter and gravitational wave detection to quantum computation. However, experiments with superfluid helium incur a high barrier to entry as they require incorporation of complex optical and electrical setups within a hermetically sealed cryogenic chamber to confine the superfluid. Here, we report on the design and construction of a helium chamber setup for operation inside a dilution refrigerator at Millikelvin temperatures, featuring electrical and optical fiber access. By incorporating an automated gas handling system, we can precisely control the amount of helium gas inserted into the chamber, rendering our setup particularly promising for experiments with superfluid helium thin films, such as superfluid thin film optomechanics. Using silicon nanophotonic resonators, we demonstrate precise control and in-situ tuning of the thickness of a superfluid helium film on the sub-nanometer level. By making use of the exceptional tunability of the superfluid film thickness, we demonstrate optomechanically induced phonon lasing of phononic crystal cavity third sound modes in the superfluid film and show that the lasing threshold crucially depends on the film thickness. The large internal volume of our chamber (V_chamber = 1l) is adaptable for integration of various optical and electrical measurement and control techniques. Therefore, our setup provides a versatile platform for a variety of experiments in fundamental and applied superfluid helium research.