Photon-noise limited sensitivity in titanium nitride kinetic inductance detectors

J. Hubmayr, J. Beall, D. Becker, H. M. Cho, M. Devlin, B. Dober, Christopher Groppi, G. C. Hilton, K. D. Irwin, D. Li, Philip Mauskopf, D. P. Pappas, J. Van Lanen, M. R. Vissers, Y. Wang, L. F. Wei, J. Gao

Research output: Contribution to journalArticle

40 Scopus citations


We demonstrate photon-noise limited performance at sub-millimeter wavelengths in feedhorn-coupled, microwave kinetic inductance detectors made of a TiN/Ti/TiN trilayer superconducting film, tuned to have a transition temperature of 1.4 K. Micro-machining of the silicon-on-insulator wafer backside creates a quarter-wavelength backshort optimized for efficient coupling at 250 μm. Using frequency read out and when viewing a variable temperature blackbody source, we measure device noise consistent with photon noise when the incident optical power is >0.5 pW, corresponding to noise equivalent powers >3 × 10-17W/√Hz. This sensitivity makes these devices suitable for broadband photometric applications at these wavelengths.

Original languageEnglish (US)
Article number073505
JournalApplied Physics Letters
Issue number7
Publication statusPublished - Feb 16 2015


ASJC Scopus subject areas

  • Physics and Astronomy (miscellaneous)

Cite this

Hubmayr, J., Beall, J., Becker, D., Cho, H. M., Devlin, M., Dober, B., ... Gao, J. (2015). Photon-noise limited sensitivity in titanium nitride kinetic inductance detectors. Applied Physics Letters, 106(7), [073505].