Squeezed light from a silicon micromechanical resonator

Author(s)

Amir H. Safavi-Naeini, Simon Gröblacher, Jeff T. Hill, Jasper Chan, Markus Aspelmeyer, Oskar Painter

Abstract

Monitoring a mechanical object’s motion, even with the gentle touch of

light, fundamentally alters its dynamics. The experimental manifestation

of this basic principle of quantum mechanics, its link to the quantum

nature of light and the extension of quantum measurement to the

macroscopic realm have all received extensive attention over the past

half-century^{1, 2}. The use of squeezed light, with quantum fluctuations below that of the vacuum field, was proposed nearly three decades ago³

as a means of reducing the optical read-out noise in precision force

measurements. Conversely, it has also been proposed that a continuous

measurement of a mirror’s position with light may itself give rise to

squeezed light^{4, 5}. Such squeezed-light generation has recently been demonstrated in a system of ultracold gas-phase atoms⁶

whose centre-of-mass motion is analogous to the motion of a mirror.

Here we describe the continuous position measurement of a solid-state,

optomechanical system fabricated from a silicon microchip and comprising

a micromechanical resonator coupled to a nanophotonic cavity. Laser

light sent into the cavity is used to measure the fluctuations in the

position of the mechanical resonator at a measurement rate comparable to

its resonance frequency and greater than its thermal decoherence rate.

Despite the mechanical resonator’s highly excited thermal state (10⁴ phonons), we observe, through homodyne detection, squeezing of the reflected light’s fluctuation spectrum at a level 4.5 ± 0.2 per cent below that of vacuum noise over a bandwidth of a few megahertz around the mechanical resonance frequency of 28 megahertz.

With further device improvements, on-chip squeezing at significant

levels should be possible, making such integrated microscale devices

well suited for precision metrology applications.

Organisation(s)

Quantum Optics, Quantum Nanophysics and Quantum Information

External organisation(s)

California Institute of Technology (Caltech), Max-Planck-Institut für die Physik des Lichts

Journal

Nature

Volume

500

Pages

185-189

No. of pages

ISSN

0028-0836

DOI

https://doi.org/10.1038/nature12307

Publication date

08-2013

Peer reviewed

Yes

Austrian Fields of Science 2012

103021 Optics, 103008 Experimental physics, 103025 Quantum mechanics

Keywords

Portal url

https://ucrisportal.univie.ac.at/en/publications/e131b005-5865-4411-b531-0d7920eaaa2c