Single-photon detectors based on the superconducting transition-edge sensor are used in a number of visible to near-infrared applications, particularly for photon-number-resolving measurements in quantum information science. To be practical for large-scale spectroscopic imaging or photonic quantum computing applications, the size of visible to near-infrared transition-edge sensor arrays and their associated readouts must be increased from a few pixels to many thousands. In this manuscript, we introduce the kinetic inductance current sensor, a scalable readout technology that exploits the nonlinear kinetic inductance in a superconducting resonator to make sensitive current measurements. Kinetic inductance current sensors can replace superconducting quantum interference devices for many applications because of their ability to measure fast, high slew-rate signals, their compatibility with standard microwave frequency-division multiplexing techniques, and their relatively simple fabrication. Here, we demonstrate the readout of a visible to near-infrared transition-edge sensor using a kinetic inductance current sensor with 3.7 MHz of bandwidth. We measure a readout noise of 1.4 pA/Hz, considerably below the detector noise at frequencies of interest, and an energy resolution of (0.137±0.001) eV at 0.8 eV, comparable to resolutions observed with non-multiplexed superconducting quantum interference device readouts.
@article{arxiv.2405.15017,
title = {Kinetic inductance current sensor for visible to near-infrared wavelength transition-edge sensor readout},
author = {Paul Szypryt and Douglas A. Bennett and Ian Fogarty Florang and Joseph W. Fowler and Andrea Giachero and Ruslan Hummatov and Adriana E. Lita and John A. B. Mates and Sae Woo Nam and Galen C. O'Neil and Daniel S. Swetz and Joel N. Ullom and Michael R. Vissers and Jordan Wheeler and Jiansong Gao},
journal= {arXiv preprint arXiv:2405.15017},
year = {2024}
}