Efficient quantum control and levitation of a nanoparticle using a novel nanophotonic interface

• Applicant: Professor Dr. Sungkun Hong
• Subject Area: Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
• Term: since 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 523178467

Quantum Optomechanics is an outstanding field in quantum science that aims to control the motions of mechanical objects at the quantum level using light-matter interaction. It offers exciting possibilities for developing new quantum technologies and probing quantum physics in new mass and length scales. Dielectric mesoscopic particles in optical tweezers have recently emerged as an excellent optomechanical system with unique qualities that could enable a new level of quantum research. The field termed levitated optomechanics or levitodynamics has rapidly progressed to enter the quantum regime in controlling the particle’s motion. However, experiments with conventional optical tweezers and cavities have not been able to bring further breakthroughs due to several outstanding problems, which include limited quantum control efficiency and instabilities arising from optical heating. The proposed research aims to develop a novel nanophotonic platform for conducting quantum experiments on the motion of a levitated. The proposed system comprises high-quality silicon nitride photonic crystal nanobeam cavities and coupling waveguides, all fabricated on a single chip. First, the nanobeam cavities will provide significantly enhanced optomechanical coupling to the particle. It thus allows for achieving quantum cooperativity above 50, an order of magnitude larger than previously reported with levitated particle systems. We will use the developed system to perform a measurement-based cooling experiment on the particle’s motion. The residual quantum fluctuation of the particle is expected to be below 0.1 motional quanta, a factor of four lower than previously achieved with the levitated nanoparticles. The strong optomechanical coupling will also enable us to construct a novel optical trap based on self-induced optomechanical backactions. We will experimentally realize it using two nanobeam cavities closely placed in parallel. The new trap will allow us to levitate a particle with substantially reduced optical heating, drastically improving the trapping stabilities and the particle’s coherence. The exceptional features of the proposed levitation and control system will provide unique opportunities for realizing outstanding quantum experiments based on levitated particles.

• DFG Programme: Research Grants
• International Connection: Netherlands
• Cooperation Partner: Dr. Simon Groeblacher