Here we will take the concepts from lecture one and set out to construct from the same Josephson junctions very weakly non-linear circuits which operate as phase-preserving amplifiers. I’ll discuss some of the numerous chall enges in designing superconducting amplifiers which are robust and simple while achieving nearly ideal performance. I’ll also discuss the quantum-limit of amplification, how closely we can approach it, and how such amplifiers allow precision readout of our quantum bits.

Page last modified: May 19, 2016