# Limitations on practical quantum cryptography

@article{Brassard2000LimitationsOP, title={Limitations on practical quantum cryptography}, author={Brassard and Lutkenhaus and Mor and Sanders}, journal={Physical review letters}, year={2000}, volume={85 6}, pages={ 1330-3 } }

We provide limits to practical quantum key distribution, taking into account channel losses, a realistic detection process, and imperfections in the "qubits" sent from the sender to the receiver. As we show, even quantum key distribution with perfect qubits might not be achievable over long distances when the other imperfections are taken into account. Furthermore, existing experimental schemes (based on weak pulses) currently do not offer unconditional security for the reported distances and…

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