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arXiv · 0808.0686

Quantum cryptography with polarization, phase and time encoding

W. T. Buttler·S. K. Lamoreaux
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Abstract

We develop and present a quantum cryptography concept in which phase determinations are made from the time that a photon is detected, as opposed to where the photon is detected, and hence is a non-interferometric process. The phase-encoded quantum information is contained in temporal and polarization superpositions of single photon states, forming a complex qudit of Hilbert dimension D equal to or greater than 4. Based on this, we have developed a new quantum key distribution protocol that allows the generation of secret key in the presence of higher noise than is possible with other protocols.

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W. T. Buttler, S. K. Lamoreaux. 2008-08-05. Quantum cryptography with polarization, phase and time encoding. https://arxiv.org/abs/0808.0686

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