Here we review recent progress in cooling micro-/nanoelectronic devices significantly below 10 mK. A number of groups worldwide are working to produce sub-millikelvin on-chip electron temperatures, motivated by the possibility of observing new physical effects and improving the performance of quantum technologies, sensors and metrological standards. The challenge is a longstanding one, with the lowest reported on-chip electron temperature having remained around 4 mK for more than 15 years. This is despite the fact that microkelvin temperatures have been accessible in bulk materials since the mid-twentieth century. In this review, we describe progress made in the last 5 years using new cooling techniques. Developments have been driven by improvements in the understanding of nanoscale physics, material properties and heat flow in electronic devices at ultralow temperatures and have involved collaboration between universities and institutes, physicists and engineers. We hope that this review will serve as a summary of the current state of the art and provide a roadmap for future developments. We focus on techniques that have shown, in experiment, the potential to reach sub-millikelvin electron temperatures. In particular, we focus on on-chip demagnetisation refrigeration. Multiple groups have used this technique to reach temperatures around 1 mK, with a current lowest temperature below 0.5 mK.

中文翻译：

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将纳米电子器件冷却至超低温的进展

在这里，我们回顾了冷却显着低于 10 mK 的微/纳米电子设备的最新进展。世界各地的许多团体都在努力生产亚毫里克尔文片上电子温度，其动机是观察新的物理效应和提高量子技术、传感器和计量标准的性能的可能性。这是一项长期存在的挑战，据报道，最低的片上电子温度保持在 4 mK 左右已超过 15 年。尽管事实上自 20 世纪中叶以来在散装材料中已经可以达到微开尔文温度。在这篇综述中，我们描述了在过去 5 年中使用新的冷却技术取得的进展。发展是由对纳米级物理学理解的改进推动的，超低温下电子设备中的材料特性和热流，涉及大学和研究所、物理学家和工程师之间的合作。我们希望这篇评论将作为当前技术状态的总结，并为未来的发展提供路线图。我们专注于在实验中显示出达到亚毫利文电子温度的潜力的技术。我们尤其专注于片上退磁制冷。多个小组已使用此技术达到 1 mK 左右的温度，目前最低温度低于 0.5 mK。我们专注于在实验中显示出达到亚毫利文电子温度的潜力的技术。我们尤其专注于片上退磁制冷。多个小组已使用此技术达到 1 mK 左右的温度，目前最低温度低于 0.5 mK。我们专注于在实验中显示出达到亚毫利文电子温度的潜力的技术。我们尤其专注于片上退磁制冷。多个小组已使用此技术达到 1 mK 左右的温度，目前最低温度低于 0.5 mK。