Nanomechanical motion measured with an imprecision below that at the standard quantum limit

Authors:
Top Cited Papers
Publisher website
Google Scholar
Abstract
Nanomechanical oscillators are at the heart of ultrasensitive detectors of force1, mass2 and motion3,4,5,6,7. As these detectors progress to even better sensitivity, they will encounter measurement limits imposed by the laws of quantum mechanics. If the imprecision of a measurement of the displacement of an oscillator8 is pushed below a scale set by the standard quantum limit, the measurement must perturb the motion of the oscillator by an amount larger than that scale. Here we show a displacement measurement with an imprecision below the standard quantum limit scale. We achieve this imprecision by measuring the motion of a nanomechanical oscillator with a nearly shot-noise limited microwave interferometer9. As the interferometer is naturally operated at cryogenic temperatures, the thermal motion of the oscillator is minimized, yielding an excellent force detector with a sensitivity of 0.51 aN Hz−1/2. This measurement is a critical step towards observing quantum behaviour in a mechanical object.
All Related Versions

This publication has 31 references indexed in Scilit: