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arXiv · 2201.11041

Quantum backaction evading measurements of a silicon nitride membrane resonator

Yulong Liu·Jingwei Zhou·Laure Mercier de Lépinay·Mika A. Sillanpää
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Abstract

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.

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Yulong Liu, Jingwei Zhou, Laure Mercier de Lépinay, Mika A. Sillanpää. 2022-01-26. Quantum backaction evading measurements of a silicon nitride membrane resonator. https://doi.org/10.1088/1367-2630/ac88ef

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