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arXiv · 2504.19747

Impossibility via W states and feasibility via W-like states for perfect quantum teleportation

Sora Kobayashi·Kei-Ichi Kondo
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Abstract

We examine the two-party perfect quantum teleportation of an unknown 1-qubit state in the case of sharing various 3-qubit entangled states between a sender and a receiver: GHZ state, W state and W-like state. We give an impossibility proof that the W state cannot be used as the sharing state to realize the perfect quantum teleportation for transmitting an arbitrary 1-qubit state, in sharp contrast with the GHZ state which is well known to realize the perfect quantum transportation. Moreover, we give a procedure of obtaining a modified entangled state which we call the W-like state to achieve the perfect quantum transportation under a prescribed measurement basis.

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Sora Kobayashi, Kei-Ichi Kondo. 2025-04-28. Impossibility via W states and feasibility via W-like states for perfect quantum teleportation. https://doi.org/10.1142/s0219749926500024

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