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Fabrication and Testing of Microfluidic Optomechanical Oscillators
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Quantum magnetomechanics: ultrahigh-Q-levitated mechanical oscillators
M Cirio1, G K Brennen, J Twamley
1Centre for Engineered Quantum Systems, Department of Physics and Astronomy, Macquarie University, North Ryde, NSW 2109, Australia.
Physical Review Letters
|October 23, 2012
Summary
We engineered a magneto-meso-mechanical quantum system with ultralong coherence times (Q~10^9) for quantum sensing. Inductive coupling to a flux qubit enables ground-state cooling, paving the way for macroscopic quantum entanglement.
Area of Science:
- Quantum mechanics
- Nanotechnology
- Quantum sensing
Background:
- Achieving ultralong motional coherence times in nanomechanical quantum systems is crucial for quantum sensing and interfaces.
- Motional noise and heating must be minimized to attain ultrahigh mechanical quality factors (Q).
Purpose of the Study:
- To examine a magneto-meso-mechanical quantum system for enhanced quantum applications.
- To investigate methods for achieving ground-state cooling and macroscopic entanglement in such systems.
Main Methods:
- Utilizing a 3D arrangement of miniature superconducting loops stably levitated in a static inhomogeneous magnetic field.
- Analyzing motional decoherence primarily caused by eddy current losses in the trapping field's magnetized sphere.
- Employing inductive coupling between the levitating object and a driven flux qubit for cooling.
Main Results:
- The system achieved ultrahigh mechanical quality factors (Q~10^9) with motional oscillation frequencies in the hundreds of kilohertz.
- Motional decoherence was predominantly attributed to eddy current losses.
- Cooling the levitating object's motion close to the ground state was demonstrated.
Conclusions:
- The magneto-meso-mechanical system exhibits properties suitable for advanced quantum applications.
- Ground-state cooling opens possibilities for generating macroscopic entangled motional states.
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