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Updated: May 17, 2026
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Optical Trapping of Nanoparticles
Published on: January 15, 2013
22.6K
Quantum control of a nanoparticle optically levitated in cryogenic free space
Felix Tebbenjohanns1, M Luisa Mattana1, Massimiliano Rossi1
1Photonics Laboratory, ETH Zürich, Zürich, Switzerland.
Nature
|July 15, 2021
Summary
Scientists achieved quantum control of a levitated nanoparticle
Area of Science:
- Quantum mechanics
- Macroscopic quantum phenomena
- Optomechanics
Background:
- Quantum control of mechanical motion is typically achieved using resonators.
- Optically levitated nanoparticles offer controllable trapping potentials for macroscopic quantum experiments.
- Previous methods relied on cavity-enhanced detection for cooling.
Purpose of the Study:
- To demonstrate quantum control over an optically levitated nanoparticle.
- To investigate quantum mechanics at macroscopic scales.
- To overcome limitations of resonator-based systems.
Main Methods:
- Optically levitating a femtogram dielectric particle in cryogenic free space.
- Utilizing measurement-based feedback for quantum control.
- Minimizing thermal effects and decoherence.
Main Results:
- Achieved quantum control over the particle's dynamics.
- Cooled the center-of-mass motion to 0.65 motional quanta.
- Reached a state purity of 0.43.
- Demonstrated dominant decoherence from measurement backaction.
Conclusions:
- Optically levitated nanoparticles enable quantum control without resonators.
- This platform facilitates macroscopic quantum mechanics investigations.
- Offers a route to transfer quantum field control to mechanical systems.
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