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arXiv · 2106.09833

Quantum communication with ultrafast time-bin qubits

Frédéric Bouchard·Duncan England·Philip J. Bustard·Khabat Heshami·Benjamin Sussman
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Abstract

The photonic temporal degree of freedom is one of the most promising platforms for quantum communication over fiber networks and free-space channels. In particular, time-bin states of photons are robust to environmental disturbances, support high-rate communication, and can be used in high-dimensional schemes. However, the detection of photonic time-bin states remains a challenging task, particularly for the case of photons that are in a superposition of different time-bins. Here, we experimentally demonstrate the feasibility of picosecond time-bin states of light, known as ultrafast time-bins, for applications in quantum communications. With the ability to measure time-bin superpositions with excellent phase stability, we enable the use of temporal states in efficient quantum key distribution protocols such as the BB84 protocol.

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Frédéric Bouchard, Duncan England, Philip J. Bustard, Khabat Heshami, Benjamin Sussman. 2021-06-17. Quantum communication with ultrafast time-bin qubits. https://arxiv.org/abs/2106.09833

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