# 1.064-um-band up-conversion single-photon detector

## TL;DR

This paper demonstrates an efficient and low-noise up-conversion single-photon detector at 1.064 μm using PPLN waveguides, with improved stability and potential applications in various fields.

## Contribution

It introduces a high-efficiency, low-noise up-conversion detector at 1.064 μm with enhanced stability by using dielectric filters instead of VBGs.

## Key findings

- Achieved 32.5% detection efficiency with 45 cps noise.
- Improved to 38% efficiency with 700 cps noise using dielectric filters.
- Demonstrated the detector's potential for practical applications.

## Abstract

Based on the technique of periodically poled lithium niobate (PPLN) waveguide, up-conversion single-photon detection at 1.064-{\mu}m is demonstrated. We have achieved a system photon detection efficiency (DE) of 32.5% with a very low noise count rate (NCR) of 45 counts per second (cps) by pumping with a 1.55-{\mu}m-band single frequency laser using the long-wavelength pumping technique and exploiting volume Bragg grating (VBG) as a narrow band filter. Replacing the VBG with a combination of adequate dielectric filters, a DE of up to 38% with a NCR of 700 cps is achieved, making the overall system more stable and practical. The up-conversion single-photon detector (SPD) operating at 1.064 {\mu}m can be a promising robust counter and find usage in many fields.

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Source: https://tomesphere.com/paper/1703.10838