Related Experiment Video
Updated: Oct 29, 2025

Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators
Published on: May 30, 2014
Quantum Oscillator Noise Spectroscopy via Displaced Cat States
Alistair R Milne1, Cornelius Hempel1, Li Li2
1ARC Centre of Excellence for Engineered Quantum Systems, The University of Sydney, School of Physics, New South Wales 2006, Australia.
Abstract:
Quantum harmonic oscillators are central to many modern quantum technologies. We introduce a method to determine the frequency noise spectrum of oscillator modes through coupling them to a qubit with continuously driven qubit-state-dependent displacements. We reconstruct the noise spectrum using a series of different drive phase and amplitude modulation patterns in conjunction with a data-fusion routine based on convex optimization. We apply the technique to the identification of intrinsic noise in the motional frequency of a single trapped ion with sensitivity to fluctuations at the sub-Hz level in a spectral range from quasi-dc up to 50 kHz.
Related Concept Videos
¹H NMR: Interpreting Distorted and Overlapping Signals
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are...
Oscillations In An LC Circuit
2D NMR: Heteronuclear Single-Quantum Correlation Spectroscopy (HSQC)
The de Broglie Wavelength
IR Spectrum Peak Splitting: Symmetric vs Asymmetric Vibrations
¹³C NMR: ¹H–¹³C Decoupling
A broadband decoupling technique is used to simplify these complex, sometimes overlapping, signals. Broadband decoupling relies on a...

