title: Upconversion detection near 2 μm at the single photon level.
abstract: We have demonstrated upconversion detection at the single photon level in the 2 μm spectral window using a pump wavelength near 1550 nm, a periodically poled lithium niobate (PPLN) waveguide, and a volume Bragg grating (VBG) to reduce noise. We achieve a system photon detection efficiency of 10%, with a noise count rate of 24,500 counts per second, competitive with other 2 μm single photon detection technologies. This detector has potential applications in environmental gas monitoring, life science, and classical and quantum communication.
authors.forename: Guo-Liang
authors.initials: GL
authors.lastname: Shentu
authors.forename: Xiu-Xiu
authors.initials: XX
authors.lastname: Xia
authors.forename: Qi-Chao
authors.initials: QC
authors.lastname: Sun
authors.forename: Jason S
authors.initials: JS
authors.lastname: Pelc
authors.forename: M M
authors.initials: MM
authors.lastname: Fejer
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhang
authors.forename: Jian-Wei
authors.initials: JW
authors.lastname: Pan