Albert Schliesser's group engineers ultracoherent phononic crystal membrane resonators with dissipation-dilution Q>10^9 and uses them for quantum optomechanics: ground-state cooling, back-action-evading measurement, optical quantum memory for single photons, and microwave-optical quantum transduction. Recent work has demonstrated a soft-clamped topological phononic waveguide (Nature 2025) and scanning force microscopy below the standard quantum limit. The group bridges fundamental quantum physics with novel sensors for electromagnetic fields and forces, and mechanical interfaces for hybrid quantum networks.
Gary Steele's lab works on quantum circuits and mechanical quantum systems, exploring quantum phenomena in nanoelectromechanical (NEMS) and superconducting circuit systems. Research includes: (1) superconducting qubit-membrane optomechanics and electromechanics; (2) circuit quantum acoustodynamics (cQAD) — coupling superconducting qubits to phonons; (3) analog quantum simulation with quantum circuits; (4) probing quantum materials (graphene, 2D materials) with superconducting circuits. The group develops novel quantum sensors for mechanical forces and electromagnetic fields.
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.
Xu leads the Experimental Quantum Engineering group with a joint ETH–PSI appointment. Research directions: (1) Superconducting circuit quantum sensing — using qubits-as-sensors for detecting weak microwave signals beyond standard quantum limits, quantum non-demolition readout of photon fields; (2) Quantum error correction enabled sensing — integrating bosonic codes (cat qubits, binomial codes) into sensing protocols; (3) Quantum acoustics — coupling superconducting qubits to surface acoustic wave (SAW) resonators for hybrid quantum sensing; (4) Novel quantum hardware at PSI — leveraging PSI's infrastructure for cryogenic device fabrication and testing. Connected to the ETH–PSI Quantum Computing Hub.
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.