| タイトル | Characterization of MgB2 Superconducting Hot Electron Bolometers |
| 著者（英） | Xi, X. X.; Wolak, M. A.; Kawamura, J. H.; Cunnane, D.; Karasik, B. S.; Acharya, N.; Tan, T. |
| 発行日 | 2014-08-10 |
| 言語 | eng |
| 内容記述 | Hot-Electron Bolometer (HEB) mixers have proven to be the best tool for high-resolution spectroscopy at the Terahertz frequencies. However, the current state of the art NbN mixers suffer from a small intermediate frequency (IF) bandwidth as well as a low operating temperature. MgB2 is a promising material for HEB mixer technology in view of its high critical temperature and fast thermal relaxation allowing for a large IF bandwidth. In this work, we have fabricated and characterized thin-film (approximately 15 nanometers) MgB2-based spiral antenna-coupled HEB mixers on SiC substrate. We achieved the IF bandwidth greater than 8 gigahertz at 25 degrees Kelvin and the device noise temperature less than 4000 degrees Kelvin at 9 degrees Kelvin using a 600 gigahertz source. Using temperature dependencies of the radiation power dissipated in the device we have identified the optical loss in the integrated microantenna responsible as a cause of the limited sensitivity of the current mixer devices. From the analysis of the current-voltage (IV) characteristics, we have derived the effective thermal conductance of the mixer device and estimated the required local oscillator power in an optimized device to be approximately 1 microwatts. |
| NASA分類 | Instrumentation and Photography; Solid-State Physics |
| レポートNO | ASC2014-1EOr1C-02 |
| 権利 | Copyright |
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