GigaHertz Centre, Department of Microtechnology and Nanoscience (MC2), Chalmers University of Technology, SE-412 96 Gothenburg, Sweden.
Departamento de Fisica Aplicada, Universidad de Salamanca, 37008 Salamanca, Spain.
Nat Mater. 2015 Feb;14(2):187-92. doi: 10.1038/nmat4126. Epub 2014 Nov 10.
Thermal dissipation at the active region of electronic devices is a fundamental process of considerable importance. Inadequate heat dissipation can lead to prohibitively large temperature rises that degrade performance, and intensive efforts are under way to mitigate this self-heating. At room temperature, thermal resistance is due to scattering, often by defects and interfaces in the active region, that impedes the transport of phonons. Here, we demonstrate that heat dissipation in widely used cryogenic electronic devices instead occurs by phonon black-body radiation with the complete absence of scattering, leading to large self-heating at cryogenic temperatures and setting a key limit on the noise floor. Our result has important implications for the many fields that require ultralow-noise electronic devices.
电子设备的有源区的热耗散是一个非常重要的基本过程。散热不足会导致温度升高到无法承受的程度，从而降低性能，因此人们正在努力减轻这种自热现象。在室温下，热阻是由于散射引起的，通常是由有源区中的缺陷和界面引起的，这阻碍了声子的传输。在这里，我们证明了在广泛使用的低温电子设备中，热量耗散是通过声子黑体辐射来实现的，完全没有散射，这导致在低温下产生很大的自热，并对噪声底限设定了关键限制。我们的结果对许多需要超低噪声电子设备的领域都有重要意义。
