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arXiv · 2506.02656

The Initial Experimental Guide to Implement QKD Polarization Encoding System at Telecom Wavelength

Zeshan Haider
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Abstract

The experimental implementation of the polarization encoding system is presented using weak coherent pulses at a low enough frequency. The optical pulses are generated through intensity modulation at the repetition rate of $10$ pulses/sec with the intensity of $7\mu W$, whose polarization is modulated by the Pockel cell. For a $ 5$ km long fiber link, the key rate is thus limited to $ 10$ bits/sec accompanied by temporal synchronization among the Intensity Modulator (IM), Pockel cell, and the gate of the detector. The system was continuously operated for $5$ minutes, and $3000$ binary bits were distributed between two nodes with an error rate less than unity. We have used only a single polarization basis, i.e., horizontal and vertical polarizations, as the objective of this experiment is to validate the feasibility of the setup under simplified conditions, intended primarily for the laboratory-scale demonstrations.

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Zeshan Haider. 2025-06-03. The Initial Experimental Guide to Implement QKD Polarization Encoding System at Telecom Wavelength. https://arxiv.org/abs/2506.02656

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