Phys.org November 20, 2019
Through the interaction of the mechanical oscillator with a microwave (or optical) cavity, back-action evading measurement in principle enables noiseless measurement of the position of the mechanical oscillator. However, additional interactions between the microwave (or optical) field and the mechanical oscillator lead to instabilities in mechanical motion, which prevents continuous measurement. Through simultaneous but unequal electromechanical amplification and cooling processes, a team of researchers in the US (industry, University of Colorado, NIST) created a method for a nearly noiseless pulsed measurement of mechanical motion. The conversion of signals between these two disparate frequency bands is important for networking future quantum computers, or to build the equivalent of the quantum internet. The research could pave the way for the development of new tools, including force-sensing technology and techniques to link quantum computers and for characterizing mechanical oscillators prepared in even more exotic quantum states, such as superposition states or cat states, a long-sought goal in the physics field…read more. Open Access TECHNICAL ARTICLE
The measuring device used by the researchers. Credit: Delaney et al.