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Updated: Jul 11, 2026
08:23
A Random-displacement Measurement by Combining a Magnetic Scale and Two Fiber Bragg Gratings
Published on: September 30, 2019
Displacement detection with a vibrating rf superconducting interference device: beating the standard linear limit
Eyal Buks1, Stav Zaitsev, Eran Segev
1Department of Electrical Engineering, Technion, Haifa 32000, Israel.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|October 13, 2007
Summary
This study demonstrates a novel displacement detector using coupled nanomechanical and superconducting resonators. Operating in a nonlinear regime enhances displacement sensitivity beyond linear limits, but reduces bandwidth.
Area of Science:
- Quantum optics
- Nanomechanical systems
- Superconducting circuits
Background:
- Displacement detection is crucial for sensitive measurements in various scientific fields.
- Superconducting quantum interference devices (SQUIDs) and resonators offer pathways for high-precision sensing.
- Nonlinear dynamics in quantum systems can lead to unique phenomena like noise squeezing.
Purpose of the Study:
- To investigate a novel displacement detector configuration.
- To analyze the impact of nonlinear resonator oscillations on displacement sensitivity.
- To explore noise squeezing and bandwidth limitations in the nonlinear regime.
Main Methods:
- Coupling a nanomechanical resonator to a radio frequency superconducting interference device and a superconducting stripline resonator.
- Employing adiabatic and rotating wave approximations for sensitivity calculations.
- Driving the stripline resonator into nonlinear oscillation and utilizing homodyne detection.
Main Results:
- The displacement sensitivity in the nonlinear regime can surpass the linear operating limit.
- Noise squeezing is observed in the output signal within the nonlinear regime.
- High displacement sensitivity is correlated with a reduced system response time, limiting bandwidth.
Conclusions:
- The studied configuration offers enhanced displacement sensitivity through nonlinear operation.
- Noise squeezing provides a mechanism for improved signal-to-noise ratio.
- A trade-off exists between sensitivity and bandwidth, necessitating careful system design for specific applications.
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