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Microwave Photonics Systems Based on Whispering-gallery-mode Resonators
Published on: August 5, 2013
Josephson junction microwave amplifier in self-organized noise compression mode.
Scientific Reports
|February 23, 2012
Summary
We developed a new Josephson junction amplifier achieving near quantum-limited noise performance at 2.8 GHz. This advancement offers a promising alternative for sensitive microwave signal detection.
Area of Science:
- Quantum physics
- Solid-state physics
- Microwave engineering
Background:
- The standard quantum limit defines the fundamental noise limit for phase-preserving amplifiers.
- Superconducting quantum interference devices and non-degenerate parametric amplifiers are leading microwave amplifier technologies, approaching but not fully reaching the quantum limit.
Purpose of the Study:
- To introduce and characterize a novel amplifier based on the negative resistance of a selectively damped Josephson junction.
- To investigate the noise performance and operational characteristics of this new amplifier design.
Main Methods:
- Utilizing a Josephson junction with selective damping to create negative resistance.
- Measuring the noise performance at 2.8 GHz.
- Employing simulations to model device characteristics and predict performance.
Main Results:
- Achieved nearly quantum-limited operation with a noise temperature of [Formula: see text] at 2.8 GHz.
- Observed that noise is primarily limited by the mixing of quantum noise from the Josephson oscillation regime to the signal frequency.
- Simulations accurately described the device's performance and suggested potential for wide bandwidth operation.
Conclusions:
- The developed Josephson junction amplifier demonstrates near quantum-limited performance, a significant step in sensitive amplification.
- Self-organization of the working point is crucial for achieving this high performance.
- The device shows promise for future applications requiring wide bandwidth, quantum-limited amplification in the microwave range.
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