Here we analyze the security of quantum dense coding protocol in which the keys are encoded on d -dimensional Hilbert space. The incoherent attack is considered during the qubits transmission through practical quantum channels. To show the performance of the protocol, the mutual information is numerically calculated under the potential eavesdropping behavior by applying a cloning-based individual attack, along with an upper bound on the error rate that ensures unconditional security against incoherent attacks.

中文翻译：

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高维量子密集编码的安全性研究

在这里，我们分析了密钥在 d 维希尔伯特空间上编码的量子密集编码协议的安全性。在通过实际量子通道传输量子比特时考虑了非相干攻击。为了显示协议的性能，通过应用基于克隆的个体攻击，在潜在的窃听行为下对互信息进行了数值计算，并确定了错误率的上限，以确保无条件安全地抵御非相干攻击。