Designed at NIST. These 25 by 15 micrometers refrigerators, are made by sandwiching a standard metal, an insulator and a superconducting metal. When a voltage is applied across, the hottest electrons burrow their way from the metal through the insulator to the superconducting metal. The temperature in the normal metal drops dramatically and drains extra heat energy from the objects being cooled.
They are not quite big enough to chill a mosquito’s six pack.
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