%0 Journal Article
%T Broadening of hot-spot response spectrum of superconducting NbN nanowire single-photon detector with reduced nitrogen content
%A Henrich, D.
%A Dorner, S.
%A Hofherr, M.
%A Il'in, K.
%A Semenov, A.
%A Heintze, E.
%A Scheffler, M.
%A Dressel, M.
%A Siegel, M.
%D 2012
%V 112
%G English
%F Henrich_etal2012
%O exported from refbase (https://db.rplab.ru/refbase/show.php?record=877), last updated on Mon, 15 Oct 2012 18:13:34 -0500
%X The spectral detection efficiency and the dark count rate of superconducting nanowiresingle-photon detectors (SNSPD) have been studied systematically on detectors made from thinNbN films with different chemical compositions. Reduction of the nitrogen content in the 4 nmthick NbN films results in a decrease of the dark count rates more than two orders of magnitudeand in a red shift of the cut-off wavelength of the hot-spot SNSPD response. The observedphenomena are explained by an improvement of uniformity of NbN films that has been confirmedby a decrease of resistivity and an increase of the ratio of the measured critical current to thedepairing current. The latter factor is considered as the most crucial for both the cut-offwavelength and the dark count rates of SNSPD. Based on our results we propose a set of criteriafor material properties to optimize SNSPD in the infrared spectral region. VC 2012 AmericanInstitute of Physics. [http://dx.doi.org/10.1063/1.4757625]
%K SSPD
%K SNSPD
%K magnetron sputtering
%K spectrum
%K NbN film
%K nitrogen concentration