Motional Sideband Asymmetry of a Solid-State Mechanical Resonator at Room Temperature
Journal article, 2025

The motional sideband asymmetry of a mechanical oscillator interacting with a laser field can be observed when approaching the quantum ground state, where the zero-point energy of the mechanical oscillator becomes a sizable contribution to its motion. In the context of quantum optomechanics, it allows, in principle, calibration-free inference of the thermal equilibrium of a macroscopic mechanical resonator with its optical bath. At room temperature, this phenomenon has been observed in pioneering experiments using levitated nanoparticles. Measuring this effect with solid-state mechanical resonators has been compounded by thermal intermodulation noise, mirror frequency noise and low quantum cooperativity. Here, we sideband-cool a membrane-in-the-middle system close to the quantum ground state from room temperature and observe motional sideband asymmetry in a dual-homodyne measurement. Sideband thermometry yields a minimum phonon occupancy of n¯eff=9.5. Our work provides insights into nonlinear optomechanical dynamics at room temperature and facilitates accessible optomechanical quantum technologies without the need for complex feedback control and cryogenic cooling.

Author

Yi Xia

Swiss Federal Institute of Technology in Lausanne (EPFL)

Guanhao Huang

Swiss Federal Institute of Technology in Lausanne (EPFL)

Harvard School of Engineering and Applied Sciences

Alberto Beccari

Swiss Federal Institute of Technology in Lausanne (EPFL)

Alessio Zicoschi

Swiss Federal Institute of Technology in Lausanne (EPFL)

Amirali Arabmoheghi

Swiss Federal Institute of Technology in Lausanne (EPFL)

Nils Johan Engelsen

Swiss Federal Institute of Technology in Lausanne (EPFL)

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Technology

Tobias J. Kippenberg

Swiss Federal Institute of Technology in Lausanne (EPFL)

Physical Review Letters

0031-9007 (ISSN) 1079-7114 (eISSN)

Vol. 134 7 073602

Subject Categories (SSIF 2025)

Atom and Molecular Physics and Optics

Condensed Matter Physics

Other Physics Topics

DOI

10.1103/PhysRevLett.134.073602

More information

Latest update

3/11/2025