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We report a model that can be used to calculate superconducting transition temperature of a transition-edge sensor (TES), which is either a normal metal–superconductor–normal metal trilayer or a normal metal–superconductor bilayer. The model allows the TC estimation of a trilayer when the normal metals at the bottom and at the top are different. Furthermore, the model includes the spin flip time of the normal metals. We use the TC calculations from this model for selected Ir-based trilayers and bilayers to help understand potential designs of low TC TESs. A Au/Ir/Au trilayer can have a low TC because the superconducting order parameter is reduced with normal metals at both sides. On the other hand, an Ir/Pt bilayer can have a low TC because the much larger electron density of states of Pt reduces the superconducting order parameter more effectively. Moreover, the spin flip scattering of paramagnetic Pt also contributes to the TC reduction. [ABSTRACT FROM PUBLISHER]

We discuss the development, at Argonne National Laboratory (ANL), of a four-pixel camera with four spectral channels centered at 150, 220, 270, and 360 GHz. The scientific motivation involves photometry of distant dusty galaxies located by Spitzer and SCUBA, as well as the study of other millimeter-wave sources such as ultra-luminous infrared galaxies, the Sunyaev-Zeldovich effect in clusters, and galactic dust. The camera incorporates Frequency Selective Bolometer (FSB) and superconducting Transition-Edge Sensor (TES) technology. The current generation of TES devices we examine utilizes proximity effect superconducting bilayers of Mo/Au, Ti, or Ti/Au as TESs, located along with frequency selective absorbing struc- tures on silicon nitride membranes. The detector incorporates lithographically patterned structures designed to address both TES device stability and detector thermal transport concerns. The membrane is not perforated, resulting in a detector which is comparatively robust mechanically. In this paper, we report on the development of the superconducting bilayer TES technology, the design and testing of the detector thermal transport and device stability control structures, optical and thermal test results, and the use of new materials. [ABSTRACT FROM AUTHOR]

We demonstrate microwave-mediated distant magnon-magnon coupling on a superconducting circuit platform, incorporating chip-mounted single-crystal Y3Fe5O12 (YIG) spheres. Coherent level repulsion and dissipative level attraction between the magnon modes of the two YIG spheres are demonstrated. The former is mediated by cavity photons of a superconducting resonator, and the latter is mediated by propagating photons of a coplanar waveguide. Our results open new avenues toward exploring integrated hybrid magnonic networks for coherent information processing on a quantum-compatible superconducting platform. [ABSTRACT FROM AUTHOR]