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Simultaneous readout of 128 X-ray and Gamma-ray Transition-edge Microcalorimeters using Microwave SQUID Multiplexing



John A. Mates, Daniel T. Becker, Douglas A. Bennett, Johnathon D. Gard, James P. Hays-Wehle, Joseph W. Fowler, Gene C. Hilton, Carl D. Reintsema, Daniel R. Schmidt, Daniel S. Swetz, Leila R. Vale, Joel N. Ullom


The number of elements in most cryogenic sensor arrays is limited by the technology available to multiplex signals from the array into a smaller number of wires and readout amplifiers. The largest demonstrated arrays of transition-edge sensor (TES) microcalorimeters contain roughly 250 detectors and use time-domain multiplexing with Superconducting Quantum Interference Devices (SQUIDs). The bandwidth limits of this technology constrain the number of sensors per amplifier chain, a quantity known as the multiplexing factor, to several 10s. With microwave SQUID multiplexing we can expand the readout bandwidth and enable much larger multiplexing factors. While microwave SQUID multiplexing of TES microcalorimeters has been previously demonstrated with small numbers of detectors, we now present a fully scalable demonstration in which 128 TES detectors are read out on a single pair of coaxial cables.
Applied Physics Letters
Created August 8, 2017, Updated March 23, 2018