Squeezed light from an oscillator measured at the rate of oscillation

Abstract

Continuous measurements of the position of an oscillator become projective on position eigenstates when the measurements are made faster than the coherent evolution. We evidence an effect of this transition on a spin oscillator within an ensemble of $2\times 10^{10}$ room-temperature atoms by observing correlations between the quadratures of the meter light field. These correlations squeeze the fluctuations of the light quadratures below the vacuum level. When the measurement is slower than the oscillation, we generate 11.5 dB and detect 8.5 dB of squeezing in a tunable band that is a fraction of the resonance frequency. When the measurement is as fast as the oscillation, we detect 4.7 dB of squeezing that spans more than one decade of frequencies below the resonance. Our results demonstrate a new regime of continuous quantum measurements on material oscillators, and set a new benchmark for the performance of a linear quantum sensor.

References in corpus (7)

• Detection of 15 dB Squeezed States of Light and their Application for the Absolute Calibration of Photoelectric Quantum Efficiency
• Observation of Radiation Pressure Shot Noise on a Macroscopic Object
• Strong relative intensity squeezing by 4-wave mixing in Rb vapor
• Quantum control of a nanoparticle optically levitated in cryogenic free space
• Light-mediated strong coupling between a mechanical oscillator and atomic spins one meter apart
• Quantum Dynamics of Collective Spin States in a Thermal Gas
• Coherent feedback cooling of a nanomechanical membrane with atomic spins

Cited by in corpus (4)

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• Transit Noise in Spin Squeezing Experiments with Coated Rubidium Vapor Cell
• Deterministic nuclear spin squeezing and squeezing by continuous measurement using vector and tensor light shifts
• Squeezing light with optomechanical and spin-light quantum interfaces