Laser cooling a membrane-in-the-middle system close to the quantum ground state from room temperature

Sampo A. Saarinen, Nenad Kralj, Eric C. Langman, Yeghishe Tsaturyan, Albert Schliesser*

*Corresponding author for this work

Research output: Contribution to journalJournal articleResearchpeer-review

12 Citations (Scopus)
26 Downloads (Pure)

Abstract

Many protocols in quantum science and technology require initializing a system in a pure quantum state. In the context of the motional state of massive resonators, this enables studying fundamental physics at the elusive quantum-classical transition, and measuring force and acceleration with enhanced sensitivity. Laser cooling has been a method of choice to prepare mechanical resonators in the quantum ground state, one of the simplest pure states. However, to overcome the heating and decoherence by the thermal bath, this usually has to be combined with cryogenic cooling. Here, we laser-cool an ultracoherent, soft-clamped mechanical resonator close to the quantum ground state directly from room temperature. To this end, we implement the versatile membrane-in-the-middle setup with one fiber mirror and one phononic crystal mirror, which reaches a quantum cooperativity close to unity already at room temperature. We further-more introduce a powerful combination of coherent and measurement-based quantum control techniques, which allows us to mitigate thermal intermodulation noise. The lowest occupancy we reach is 30 phonons, limited by measurement imprecision. Doing away with the necessity for cryogenic cooling should further facilitate the spread of optomechanical quantum technologies. (c) 2023 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement

Original languageEnglish
JournalOptica
Volume10
Issue number3
Pages (from-to)364-372
Number of pages9
ISSN2334-2536
DOIs
Publication statusPublished - 20 Mar 2023

Keywords

  • OPTOMECHANICAL SYSTEM
  • CAVITY
  • RESONATORS
  • OSCILLATOR
  • MOTION

Cite this