Kuo Paulina S
Information Technology Laboratory, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, Maryland 20899, USA.
OSA Contin. 2018;1. doi: 10.1364/OSAC.1.001260.
There is growing interest in superconducting nanowire single-photon detectors (SNSPDs) for their high detection efficiency, low noise, and broad wavelength-sensitivity range. Typically, silica fibers are used to deliver light to the detectors inside the cryostat, which works well for wavelengths from visible through 1550 nm. To access longer-wavelength infrared photons, other types of fibers, such as chalcogenide and fluoride fibers, need to be used. Here, we examine the infrared-wavelength transmission of straight and coiled silica optical fibers as candidates to couple infrared light to SNSPDs. We find that the silica fibers offer good transmission up to 2.2 m wavelength. Above this wavelength, the transmission rolls off; the fibers exhibit 3 dB/m loss at 2.5 m. High bend-loss sensitivity of some fibers can be used to adjust the long-wavelength transmission cutoff of the fiber to limit noise photons due to blackbody radiation.
超导纳米线单光子探测器（SNSPD）因其高探测效率、低噪声和宽波长敏感范围而受到越来越多的关注。通常，石英光纤用于将光传输到低温恒温器内的探测器，这对于从可见光到1550纳米的波长都能很好地工作。为了探测更长波长的红外光子，需要使用其他类型的光纤，如硫系光纤和氟化物光纤。在此，我们研究了直的和盘绕的石英光纤在将红外光耦合到SNSPD方面的红外波长传输特性。我们发现，石英光纤在波长高达2.2米时具有良好的传输性能。超过这个波长，传输率下降；这些光纤在2.5米处的损耗为3分贝/米。一些光纤的高弯曲损耗敏感性可用于调整光纤的长波长传输截止，以限制由于黑体辐射产生的噪声光子。
