Design of a flux buffer based on the flux shuttle

The design considerations for a flux buffer based on the flux shuttle concept are discussed. Particular attention is given to the issues of flux popping, stability of operation, and saturation levels for a large input. Modulation techniques used in order to minimize 1/f noise, in addition to offsets, are analyzed. Advantages over conventional approaches using a SQUID for a flux buffer are discussed. Results of computer simulations are presented.