article published yes Kristen W Galvin author 41737c86-5355-11ee-ae5a-d2146bfd0877 Anton Bubis author 1f6212b5-f795-11ec-9c0c-de4780302890 Melissa Mikalsen author William F. Schiela author Bassel H. Elfeky author William M. Strickland author Duc T Phan author 29C8C0B4-F248-11E8-B48F-1D18A9856A87 Javad Shabani author Andrew P Higginbotham author 4AD6785A-F248-11E8-B48F-1D18A9856A870000-0003-2607-2363 GradSch department AnHi department GeKa department Center for Correlated Quantum Materials and Solid State Quantum Systems: Conventional and unconventional topological superconductors project Arrays of Josephson junctions can be tuned through anomalous metallic, quantum-critical, and insulating regimes. We introduce an alternative experimental probe, capturing microwave radiation across all three regimes, using a two-dimensional array of superconductor-semiconductor hybrid Josephson junctions as a model system. Our approach allows calibration of the sample’s circuit parameters and provides isolation from measurement back-action effects. We measure the radiation temperature of the anomalous metal and find that it is hotter than both the quantum-critical and insulating regimes. We further show that the anomalous metallic regime is more susceptible to additional heating than other regimes, explaining its emergence in otherwise thermalized systems. Turning to the quantum-critical regime, we discover nonlinear scaling of radiative noise with applied bias, consistent with theoretical predictions of universal nonequilibrium behavior at quantum-critical points. https://research-explorer.ista.ac.at/download/22323/22350/2026_PhysicalReviewApplied_Leonard.pdf application/pdfno American Physical Society2026 eng 2331-7019 2409.0983510.1103/75bl-mm3b 26 Galvin, Kristen W., et al. “Microwave Radiometry of a Quantum-Critical Hybrid Josephson Array.” <i>Physical Review Applied</i>, vol. 26, 014031, American Physical Society, 2026, doi:<a href="https://doi.org/10.1103/75bl-mm3b">10.1103/75bl-mm3b</a>. Galvin, Kristen W, Anton Bubis, Melissa Mikalsen, William F. Schiela, Bassel H. Elfeky, William M. Strickland, Duc T Phan, Javad Shabani, and Andrew P Higginbotham. “Microwave Radiometry of a Quantum-Critical Hybrid Josephson Array.” <i>Physical Review Applied</i>. American Physical Society, 2026. <a href="https://doi.org/10.1103/75bl-mm3b">https://doi.org/10.1103/75bl-mm3b</a>. K. W. Galvin <i>et al.</i>, “Microwave radiometry of a quantum-critical hybrid Josephson array,” <i>Physical Review Applied</i>, vol. 26. American Physical Society, 2026. Galvin, K. W., Bubis, A., Mikalsen, M., Schiela, W. F., Elfeky, B. H., Strickland, W. M., … Higginbotham, A. P. (2026). Microwave radiometry of a quantum-critical hybrid Josephson array. <i>Physical Review Applied</i>. American Physical Society. <a href="https://doi.org/10.1103/75bl-mm3b">https://doi.org/10.1103/75bl-mm3b</a> Galvin KW, Bubis A, Mikalsen M, Schiela WF, Elfeky BH, Strickland WM, Phan DT, Shabani J, Higginbotham AP. 2026. Microwave radiometry of a quantum-critical hybrid Josephson array. Physical Review Applied. 26, 014031. K.W. Galvin, A. Bubis, M. Mikalsen, W.F. Schiela, B.H. Elfeky, W.M. Strickland, D.T. Phan, J. Shabani, A.P. Higginbotham, Physical Review Applied 26 (2026). Galvin KW, Bubis A, Mikalsen M, et al. Microwave radiometry of a quantum-critical hybrid Josephson array. <i>Physical Review Applied</i>. 2026;26. doi:<a href="https://doi.org/10.1103/75bl-mm3b">10.1103/75bl-mm3b</a> 223232026-07-14T05:35:24Z2026-07-16T09:41:27Z