Hyperspectral photon-counting optical time domain reflectometry

Abstract

Optical time-domain reflectometry (OTDR) is one of the most used techniques for nondestructive characterization of optical fiber links. Although conventional OTDR exhibits good performance in classical network applications, photoncounting OTDR (ν-OTDR) offers a promising way for in-situ optical channel characterization of quantum network fibers where single-photon detectors are present. ν-OTDR has been demonstrated at the telecommunication wavelengths of 1310 and 1550 nm. Here, we present our hyperspectral ν-OTDR measurement covering a wavelength range from 1150 nm to 1800 nm. The results show low attenuation in SMF-28 fiber between 1150 nm and 1700 nm of less than 0.5 dB/km. However, we show that connector loss can worsen significantly for wavelengths greater than 1550 nm.