Skip to main content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.


The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

A titanium-nitride near-infrared kinetic inductance photon-counting detector and its anomalous electrodynamics



Martin O. Sandberg, Fabio C. Da Silva, Kent D. Irwin, David P. Pappas, Sae Woo Nam, David Wisbey, Ben Mazin, Seth Meeker, Jonas Zmuidzinas, Henry G. Leduc


We demonstrate single-photon counting at 1550 nm with titanium-nitride (TiN) microwave kinetic inductancedetectors. Full-width-at-half-maximum energy resolution of 0.4 eV is achieved. 0-, 1-, 2- photon events are resolved and shown to follow Poisson statistics. We find that the temperature- dependent frequency shift deviates from the Mattis-Bardeen theory, and the dissipation response shows a shorter decay time than the frequency response at low temperatures. We suggest that the observed anomalous electrodynamics may be related to quasiparticle traps or subgap states in the disordered TiN films. Finally, the electron density-of-states is derived from the pulse response.
Applied Physics Letters


kinetic inductance detector, single photon detector, titanium nitride
Created October 1, 2012, Updated November 10, 2018