1. Impact of Electrical Contacts Design and Materials on the Stability of Ti Superconducting Transition Shape
- Author
-
Volodymyr Yefremenko, Trupti Khaire, Joshua Montgomery, A. Cukierman, Stephen S. Meyer, Peter A. R. Ade, Zeeshan Ahmed, K. T. Story, Nathan Whitehorn, Faustin Carter, W. B. Everett, Erik Shirokoff, H. Nguyen, Junjia Ding, G. I. Noble, Gene C. Hilton, Jason E. Austermann, Graeme Smecher, Q. Y. Tang, Carole Tucker, Ralu Divan, M. Korman, A. M. Kofman, Alexandra S. Rahlin, J. A. Sobrin, Adam Anderson, Andrew Nadolski, I. Shirley, N. Huang, A. Gilbert, N. L. Harrington, Amy N. Bender, Ki Won Yoon, D. Dutcher, Antony A. Stark, John E. Carlstrom, Michelle Jonas, Angelina H. Harke-Hosemann, C. S. Miller, N. W. Halverson, Oliver Jeong, Matt Dobbs, Bradford Benson, Z. Pan, A. E. Lowitz, C. L. Chang, Valentine Novosad, Adrian T. Lee, Jean Francois Cliche, Daniel Michalik, K. Vanderlinde, Gensheng Wang, Keith L. Thompson, Jason W. Henning, Kent D. Irwin, W. L. Holzapfel, Donna Kubik, Tijmen de Haan, C. M. Posada, Steve Kuhlmann, Joaquin Vieira, John E. Pearson, Aritoki Suzuki, Thomas Cecil, J. T. Sayre, Liliana Stan, Jessica Avva, Stephen Padin, E. V. Denison, T. Natoli, J. E. Ruhl, Leila R. Vale, Robitan Basu Thakur, L. J. Saunders, A. Foster, Chao-Lin Kuo, John Groh, R. N. Gannon, and M. R. Young
- Subjects
Superconductivity ,Reproducibility ,Materials science ,Condensed matter physics ,Scanning electron microscope ,Bolometer ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,Electrical contacts ,law.invention ,Differential interference contrast microscopy ,law ,0103 physical sciences ,General Materials Science ,Diffusion (business) ,Transition edge sensor ,010306 general physics ,0210 nano-technology - Abstract
The South Pole Telescope SPT-3G camera utilizes Ti/Au transition edge sensors (TESs). A key requirement for these sensors is reproducibility and long-term stability of the superconducting (SC) transitions. Here, we discuss the impact of electrical contacts design and materials on the shape of the SC transitions. Using scanning electron microscope, atomic force microscope, and optical differential interference contrast microscopy, we observed the presence of unexpected defects of morphological nature on the titanium surface and their evolution in time in proximity to Nb contacts. We found direct correlation between the variations of the morphology and the SC transition shape. Experiments with different diffusion barriers between TES and Nb leads were performed to clarify the origin of this problem. We have demonstrated that the reproducibility of superconducting transitions can be significantly improved by preventing diffusion processes in the TES–leads contact areas.
- Published
- 2018
- Full Text
- View/download PDF