Quantum key distribution using multilevel encoding
Mohamed Bourennane, Anders L. Karlsson, Gunnar G. Bjork · Physical Review A · 2001
In this article, protocols for quantum key distribution based on encoding in higher dimensional systems in N-dimensional Hilbert space are proposed. We extend the original Bennett-Brassard protocol using two complementary bases and two-dimensional states to M mutually complementary bases and N orthogonal vectors in each base. We study the mutual information between the legitimate parties and the eavesdropper and the error rate by considering various incoherent eavesdropping attacks as a function of the dimension of the Hilbert space.