Quantum backaction disturbs the measurement of the position of a mechanical oscillator by introducing additional fluctuations. In a quantum backaction measurement technique, the backaction can be evaded, although at the cost of losing part of the information. In this work, we carry out such a quantum backaction measurement using a large 0.5 mm diameter silicon nitride membrane oscillator with 707 kHz frequency, via a microwave cavity readout. The measurement shows that quantum backaction noise can be evaded in the quadrature measurement of the motion of a large object.
@article{arxiv.2201.11041,
title = {Quantum backaction evading measurements of a silicon nitride membrane resonator},
author = {Yulong Liu and Jingwei Zhou and Laure Mercier de Lépinay and Mika A. Sillanpää},
journal= {arXiv preprint arXiv:2201.11041},
year = {2022}
}