Ultrafast all-optical quantum teleportation

Takumi Suzuki; Takaya Hoshi; Akito Kawasaki; Shotaro Oki; Konhi Ichii; Hironari Nagayoshi; Kazuma Takahashi; Takahiro Kashiwazaki; Taichi Yamashima; Asuka Inoue; Takeshi Umeki; Tatsuki Sonoyama; Kan Takase; Warit Asavanant; Mamoru Endo; Akira Furusawa

arXiv · 2604.14959

Ultrafast all-optical quantum teleportation

Takumi Suzuki·Takaya Hoshi·Akito Kawasaki·Shotaro Oki·Konhi Ichii·Hironari Nagayoshi·Kazuma Takahashi·Takahiro Kashiwazaki·Taichi Yamashima·Asuka Inoue·Takeshi Umeki·Tatsuki Sonoyama·Kan Takase·Warit Asavanant·Mamoru Endo·Akira Furusawa

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Abstract

Light's intrinsic carrier frequency of hundreds of terahertz theoretically enables information processing at terahertz clock rates. In optical quantum computing, continuous-variable quantum teleportation is the fundamental building block for deterministic logic operations. This protocol transfers unknown quantum states between nodes using quantum entanglement and real-time feedforward of measurement outcomes. However, electrical feedforward bottlenecks currently restrict operational bandwidths to approximately 100 megahertz, preventing the exploitation of light's ultimate speed. Here we show 1-terahertz-bandwidth all-optical quantum teleportation, completely bypassing this electronic limitation. By transferring Bell measurement outcomes optically, we successfully teleported vacuum states across the terahertz band and real-time random coherent wavepackets with a 42-picosecond temporal width. Evaluating the intrinsic state transfer quality, we achieved teleportation fidelities of $\mathcal{F}=0.784$ for the broadband vacuum states and $\mathcal{F}=0.770$ for the dynamic coherent wavepackets. Both results strictly surpass the classical limit of $\mathcal{F}=0.5$, demonstrating genuine quantum teleportation at ultrafast speeds. Our results establish that optical quantum processing speeds are constrained solely by the nonlinear medium's 1-picosecond-scale response, rather than classical electrical interfaces. This methodology provides a cornerstone for terahertz-clock quantum computers capable of overcoming Moore's law, and paves the way for a high-capacity, telecom-compatible quantum internet.

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Takumi Suzuki, Takaya Hoshi, Akito Kawasaki, Shotaro Oki, Konhi Ichii, Hironari Nagayoshi, Kazuma Takahashi, Takahiro Kashiwazaki, Taichi Yamashima, Asuka Inoue, Takeshi Umeki, Tatsuki Sonoyama, Kan Takase, Warit Asavanant, Mamoru Endo, Akira Furusawa. 2026-04-16. Ultrafast all-optical quantum teleportation. https://arxiv.org/abs/2604.14959

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