Time-bin encoded quantum key distribution over 120 km with a telecom quantum dot source

Jipeng Wang; Joscha Hanel; Zenghui Jiang; Raphael Joos; Michael Jetter; Eddy Patrick Rugeramigabo; Simone Luca Portalupi; Peter Michler; Xiao-Yu Cao; Hua-Lei Yin; Lei Shan; Jingzhong Yang; Michael Zopf; Fei Ding

doi:10.1038/s41377-026-02205-9

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Time-bin encoded quantum key distribution over 120 km with a telecom quantum dot source

Original Articles

- Time-bin encoded quantum key distribution over 120 km with a telecom quantum dot source
- Light: Science & Applications Vol. 15, Issue 4, Pages: 1064-1075(2026)
- Affiliations：
  
  1.Institut für Festkörperphysik, Leibniz Universität Hannover, Appelstraße 2, 30167 Hannover, Germany
  2.Institut für Halbleiteroptik und Funktionelle Grenzflächen, Center for Integrated Quantum Science and Technology (IQST) and SCoPE, University of Stuttgart, Allmandring 3, 70569 Stuttgart, Germany
  3.National Laboratory of Solid State Microstructures and School of Physics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, 210093 Nanjing, China
  4.Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials and Micro-nano Devices, Key Laboratory of Quantum State Construction and Manipulation (Ministry of Education), Renmin University of China, 100872 Beijing, China
  5.Information Materials and Intelligent Sensing Laboratory of Anhui Province, Institutes of Physical Science and Information Technology, Anhui University, 230601 Hefei, China
  6.Laboratorium für Nano- und Quantenengineering, Leibniz Universität Hannover, Schneiderberg 39, 30167 Hannover, Germany
- Author bio：
  
  Jingzhong Yang (jingzhong.yang@fkp.uni-hannover.de)
- Funds：
- DOI：10.1038/s41377-026-02205-9
  CLC：
- Received：27 August 2025，
  
  Revised：2026-01-20，
  
  Accepted：21 January 2026，
  
  Online First：25 February 2026，
  
  Published：30 April 2026
- Accepted：
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Wang, J. P. et al. Time-bin encoded quantum key distribution over 120 km with a telecom quantum dot source. Light: Science & Applications, 15, 1064-1075 (2026).
DOI：

Wang, J. P. et al. Time-bin encoded quantum key distribution over 120 km with a telecom quantum dot source. Light: Science & Applications, 15, 1064-1075 (2026). DOI： 10.1038/s41377-026-02205-9.

摘要

Abstract

Quantum key distribution (QKD) with deterministic single photon sources has been demonstrated over intercity fiber and free-space channels. The previous implementations relied mainly on polarization encoding schemes

which are susceptible to birefringence

polarization-mode dispersion and polarization-dependent loss in practical fiber networks. In contrast

time-bin encoding offers inherent robustness and has been widely adopted in mature QKD systems using weak coherent laser pulses. However

its feasibility in conjunction with a deterministic single-photon source has not yet been experimentally demonstrated. In this work

we construct a time-bin encoded QKD system employing a high-brightness quantum dot (QD) single-photon source operating at telecom wavelength. Our proof-of-concept experiment successfully demonstrates the possibility of secure key distribution over fiber link of 120 km

while maintaining extraordinary long-term stability over 6 h of continuous operation

that is highest secure key rate among the time-bin QKDs based on single-photon sources. This work provides the first experimental validation of integrating a QD single-photon source with time-bin encoding in a telecom-band QKD system. This development signifies a substantial advancement in the establishment of a robust and scalable QKD network based on solid-state single-photon technology.

关键词

Keywords

references

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