TY - CONF AU - Korneev, Alexander AU - Korneeva, Yulia AU - Florya, Irina AU - Elezov, Michael AU - Manova, Nadezhda AU - Tarkhov, Michael AU - An, Pavel AU - Kardakova, Anna AU - Isupova, Anastasiya AU - Chulkova, Galina AU - Voronov, Boris PY - 2011 DA - 2011// TI - Recent advances in superconducting NbN single-photon detector development T2 - Proc. SPIE BT - Proc. SPIE SP - 807202 (1 to 10) VL - 8072 KW - SSPD AB - Superconducting single-photon detector (SSPD) is a planar nanostructure patterned from 4-nm-thick NbN film deposited on sapphire substrate. The sensitive element of the SSPD is 100-nm-wide NbN strip. The device is operated at liquid helium temperature. Absorption of a photon leads to a local suppression of superconductivity producing subnanosecond-long voltage pulse. In infrared (at 1550 nm and longer wavelengths) SSPD outperforms avalanche photodiodes in terms of detection efficiency (DE), dark counts rate, maximum counting rate and timing jitter. Efficient single-mode fibre coupling of the SSPD enabled its usage in many applications ranging from single-photon sources research to quantum cryptography. Recently we managed to improve the SSPD performance and measured 25% detection efficiency at 1550 nm wavelength and dark counts rate of 10 s-1. We also improved photon-number resolving SSPD (PNR-SSPD) which realizes a spatial multiplexing of incident photons enabling resolving of up to 4 simultaneously absorbed photons. Another improvement is the increase of the photon absorption using a λ/4 microcavity integrated with the SSPD. And finally in our strive to increase the DE at longer wavelengths we fabricated SSPD with the strip almost twice narrower compared to the standard 100 nm and demonstrated that in middle infrared (about 3 μm wavelength) these devices have DE several times higher compared to the traditional SSPDs. N1 - exported from refbase (https://db.rplab.ru/refbase/show.php?record=663), last updated on Tue, 04 May 2021 21:23:00 -0500 ID - Korneev_etal2011 ER -