Abstract
The fundamental noise limit of a phase-preserving amplifier at frequency is the standard quantum limit. In the microwave range, the best candidates have been amplifiers based on superconducting quantum interference devices (reaching the noise temperature at 700 MHz), and non-degenerate parametric amplifiers (reaching noise levels close to the quantum limit at 8 GHz). We introduce a new type of an amplifier based on the negative resistance of a selectively damped Josephson junction. Noise performance of our amplifier is limited by mixing of quantum noise from Josephson oscillation regime down to the signal frequency. Measurements yield nearly quantum-limited operation, at 2.8 GHz, owing to self-organization of the working point. Simulations describe the characteristics of our device well and indicate potential for wide bandwidth operation.
| Original language | English |
|---|---|
| Article number | 276 |
| Journal | Scientific Reports |
| Volume | 2 |
| DOIs | |
| Publication status | Published - 2012 |
| MoE publication type | A1 Journal article-refereed |
Funding
This work was supported by Center of Excellence and Materials World Network grants of the Academy of Finland and by the European Science Foundation (ESF) under the EUROCORES Programme EuroGRAPHENE.
Keywords
- Applied physics
- electronic materials and devices
- quantum physics
- superconducting materials