0000000000386690
AUTHOR
L. Oberto
Noise Figures of Merit of rf-SQUID-based Josephson Travelling Wave Parametric Amplifiers
The characterization of the rf-SQUID-based JTWPA in terms of its noise figure and gain for different input states (Fock states or Coherent states) has been carried out. The spectral distribution of the noise temperature Tn and gain G presents a region where the amplifier has a relatively high gain with a thermal noise that can go beyond the standard quantum limit =ℏ/2 (valid only for single mode input states [44]) as shown in Fig. 3. The TWJPA is here biased in its 3WM regime and pumped at p = 12 GHz.
Bimodal Approach for Noise Figures of Merit Evaluation in Quantum-Limited Josephson Traveling Wave Parametric Amplifiers
The advent of ultra-low noise microwave amplifiers revolutionized several research fields demanding quantum-limited technologies. Exploiting a theoretical bimodal description of a linear phase-preserving amplifier, in this contribution we analyze some of the intrinsic properties of a model architecture (i.e., an rf-SQUID based Josephson Traveling Wave Parametric Amplifier) in terms of amplification and noise generation for key case study input states (Fock and coherents). Furthermore, we present an analysis of the output signals generated by the parametric amplification mechanism when thermal noise fluctuations feed the device.