Doubling photon-processing power for MKID readout

Microwave Kinetic Inductance Detectors (MKIDs) are superconducting detectors capable of counting single photons while measuring their energy and arrival time down to the microsecond. These detectors have applications in quantum computing, biological imaging, and astronomical observations – however, large MKID arrays require readout systems capable of processing many signals simultaneously and in real time.

Smith et al. created and experimentally demonstrated a complete readout platform that, compared to previous systems, can process twice as many MKIDs with 10 times lower power, weight, volume, and cost-per-pixel. The platform, known as the third-generation MKID readout system, or MKIDGen3, leverages a new Radio-Frequency System-on-Chip (RFSoC) technology.

“This work provides a detailed reference for solving problems related to the RFSoC platform, which is widely sought after as a technology target for large-bandwidth, real-time RF signal processing applications, such as 5G/6G wireless, quantum computing, and cryogenic detector arrays,” said author Jennifer Smith. “The fully open-source design will enable other groups to get a jump-start with the RFSoC and allow pieces of the design to be reused.”

MKIDGen3 can be used for a wide range of applications that require single-photon detection with high resolution and a large number of channels, as well as to design future MKIDs and other cryogenic detector readout systems. This platform will also aid the effort to scale up readout arrays for MKIDs that could potentially be used in space-based astrophysical measurements of the future.

“This work provides a breakthrough in MKID readout technology with a maintainable, scalable platform from which we can work towards megapixel MKID arrays and future space-based deployment,” Smith said.

Source: “MKIDGen3: Energy-resolving, single-photon-counting microwave kinetic inductance detector readout on a radio frequency system-on-chip,” by Jennifer Pearl Smith, John I. Bailey, III., Aled Cuda, Nicholas Zobrist, and Benjamin A. Mazin, Review of Scientific Instruments (2024). The article can be accessed at https://doi.org/10.1063/5.0225768 .