Thermionic junction devices utilizing phonon blocking

• DOI: 10.1126/sciadv.aax9191
• Publication Date: 2020-04-10T23:17:54Z
• Authors: Emma Mykkänen; Janne S. Lehtinen; Leif Grönberg; Andrey Shchepetov; Andrey V. Timofeev; David Gunnarsson; Antti Kemppinen; Antti J. Manninen; Mika Prunnila
• Keywords: Thermionic emission; Blocking (statistics)

Electrothermal elements are used in various energy harvesters, coolers, and radiation detectors. The optimal operation of these relies on mastering two competing boundary conditions: the maximization electrothermal response blockade lattice (phonon) thermal conduction. In this work, we propose demonstrate that efficient phonon blocking can be achieved solid-state thermionic junctions, paving way for new phonon-engineered high-efficiency refrigerators sensors. Our experimental demonstration uses semiconductor-superconductor (Sm-S) junctions where arises from superconducting gap results acoustic transmission bottleneck at junction. We a cooling platform silicon chip, suspended only Sm-S is cooled by ~40% bath temperature. also show how observed effect detectors multistage electronic suitable quantum technology devices.