Technique - (14) Pulsed optomechanics / back-action-evading measurement

Type: Experimental

Description: Pulsed radiation-pressure interactions for back-action-evading position measurement, mechanical state squeezing, and quantum state tomography of nano/micromechanical resonators.

Department(s)/lab(s): Physics – QOLS / Light Community | Quantum Measurement Lab (Vanner) @ Imperial
Summary:

Vanner leads the Quantum Measurement Lab, combining experiment and theory. Key research areas: (1) Cavity quantum optomechanics — developed a theoretical framework capturing nonlinear radiation-pressure beyond the linearised approximation, showing deterministic mechanical Wigner-negativity generation; demonstrated mechanical position-squared measurements in Nature Comms (2016); thermal noise squeezing by 36 dB (Nat. Comms 2013); (2) Brillouin-Mandelstam scattering — demonstrated strong coupling to high-frequency phonons (Optica 2019); single-phonon addition/subtraction via Brillouin (PRL 2021); quantum state tomography with non-Gaussianity; (3) Hybrid quantum systems — 'displacemon' architecture (nanobeam magnetically coupled to superconducting qubit, PRX 2018) for testing objective collapse and dark matter; (4) Quantum gravity tests — proposals for testing the generalised uncertainty principle (GUP) using optomechanical protocols. UKRI QTFP fellowship.

Department(s)/lab(s): Physics | LuMIn - Nano-optomechanics (Verlot) @ ENSPS
Summary:

Verlot works on nano-optomechanics and quantum-limited displacement/force sensing with nanowire and levitated resonators, exploring ultrasensitive force detection and fundamental measurement limits. In the broader landscape of NV-centre ensemble quantum sensing (DEER, nano-NMR, T1 relaxometry) operating near pT/sqrt(Hz) sensitivity, this work is complemented by mechanical quantum sensors at the force-sensitivity frontier.

Department(s)/lab(s): Electrical & Electronic Engineering – Photon Science Institute | Quantum Engineering Lab (Vijayan Group) @ Manchester
Summary:

Vijayan leads the Quantum Engineering Lab at Manchester's Photon Science Institute, focusing on levitated optomechanics. Key results: (1) Programmable cavity-mediated long-range interactions between two levitated nanoparticles via coherently scattered photons (Nature Physics 2024, ETH Zurich/Innsbruck collaboration before Manchester); (2) Ground-state cooling of nanospheres and building toward quantum superpositions; (3) Quantum sensing with levitated systems — ultra-sensitive force/acceleration detectors; dark matter searches with nanoparticle momentum transfer detection (QTFP-funded collaboration with Darren Price); (4) Multi-particle quantum arrays. Royal Society University Research Fellow. Currently advertising PhD positions in quantum sensing with levitated optomechanical systems. Collaborates with Novotny (ETH), Romero-Isart (Innsbruck), and Millen (King's College London).

Department(s)/lab(s): Physics / Niels Bohr Institute | Copenhagen Center for Biomedical Quantum Sensing (CBQS) @ UCPH
Summary:

Emil Zeuthen works on theoretical quantum optomechanics and quantum transduction. Research focuses on (1) figures of merit and protocols for quantum transducers (mechanical interfaces between microwave and optical domains); (2) back-action-evading measurements using optomechanical systems; (3) quantum limits for gravitational wave detection with mechanical systems in a negative-mass spin reference frame. Key QUANTOP theory collaborator bridging optomechanics and quantum sensing.