Related Experiment Video
Updated: Feb 6, 2026

Fabrication and Testing of Microfluidic Optomechanical Oscillators
Published on: May 29, 2014
Demonstration of an Effective Ultrastrong Coupling between Two Oscillators
D Marković1, S Jezouin1, Q Ficheux1,2
1Département de physique de l'ENS, Laboratoire Pierre Aigrain, École normale supérieure, PSL Research University, Université Paris Diderot, Sorbonne Paris Cité, Sorbonne Universités, UPMC University Paris 06, CNRS, 75005 Paris, France.
Abstract:
When the coupling rate between two quantum systems becomes as large as their characteristic frequencies, it induces dramatic effects on their dynamics and even on the nature of their ground state. The case of a qubit coupled to a harmonic oscillator in this ultrastrong coupling regime has been investigated theoretically and experimentally. Here, we explore the case of two harmonic oscillators in the ultrastrong coupling regime. Probing the properties of their ground state remains out of reach in natural implementations. Therefore, we have realized an analog quantum simulation of this coupled system by dual frequency pumping a nonlinear superconducting circuit. The pump amplitudes directly tune the effective coupling rate. We observe spectroscopic signature of a mode hybridization that is characteristic of the ultrastrong coupling. We experimentally demonstrate a key property of the ground state of this simulated ultrastrong coupling between modes by observing simultaneous single- and two-mode squeezing of the radiated field below vacuum fluctuations.
Related Concept Videos
Oscillations In An LC Circuit
Forced Oscillations
Damped Oscillations
Although friction and other non-conservative...
Oscillations about an Equilibrium Position
Limits with Oscillating Discontinuities
Spin–Spin Coupling: Two-Bond Coupling (Geminal Coupling)
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...

