NIST physicists have developed a new method to cool a microscopic mechanical drum to temperatures below the quantum limit, using a technique called sideband cooling with squeezed light. The drum, made of aluminum and measuring 20 micrometers in diameter, was cooled to less than one-fifth of a single quantum unit of energy below the previously thought possible limit.
The new cooling method involves using squeezed light to drive the drum circuit, which reduces unwanted intensity fluctuations and inadvertently heating of the drum. This approach removes the generally accepted cooling limit for large or low-frequency objects, making it easier to cool them to absolute zero temperatures.
The cooled drum could potentially be used in hybrid quantum computers combining both quantum and mechanical elements, as well as in more sensitive sensors and longer information storage. The research was published in the January 12, 2017 issue of Nature.
Keywords: Squeezed light, Quantum fluctuations, Sideband cooling, Phonon, Quantum limit
