Heat Transfer Sets the Noise Floor for Ultrasensitive Electronics

Austin Minnich, Assistant Professor of Mechanical Engineering and Applied Physics, and colleagues have identified a source of electronic noise that could affect the functioning of instruments operating at very low temperatures, such as devices used in radio telescopes and advanced physics experiments. The team's findings also suggest that it may be possible to develop engineering strategies to make phonon heat transfer more efficient at low temperatures. For example, one possibility might be to change the design of transistors so that phonon generation takes place over a broader volume. "If you can make the phonon generation more spread out, then in principle you could reduce the temperature rise that occurs," Professor Minnich says. "We don't know what the precise strategy will be yet, but now we know the direction we should be going. That's an improvement." [Caltech release]