Waveform analysis of a large-area superconducting nanowire single photon detector
Abstract
Superconducting nanowire single photon detectors (SNSPDs) are typically used as single-mode-fiber-coupled single-pixel detectors, but large area detectors are increasingly critical for applications ranging from microscopy to free-space quantum communications. However, the long meander-line length of such large-area SNSPDs results in a proportionately large kinetic inductance that affects the waveform generated by the device. Here, we explore changes in the rising edge of the readout pulse for a single-pixel large-area SNSPD as a function of the optical spot size on the detector and compare to the rising edge of the dark-count waveform. We observe a bimodal distribution of bright-count rise times and show that the probability of a slow rise time increases in the limit of large spot sizes, indicative of a position sensitive response. Additionally, in the limit of low bias currents, the dark-count readout pulse is most similar to the large spot-size bright-count readout pulse, which suggests that dark counts arise from locations spanning the device. These results are consistent with a simple model of traveling microwave modes excited by single photons incident at varying positions along the length of the nanowire.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Feb 02, 2021
- Source ID
- 10.1088/1361-6668/abd150
Entities
People
- Aaron J. Miller
- Alexander A Puretzky
- Ben Lawrie
- Brian E. Lerner
- Claire E. Marvinney
Organizations
- Intelligence Community Postdoctoral Research Fellowship Program
- Oak Ridge National Laboratory
- Office of Basic Energy Sciences
- United States Department of Energy