Quantum Key Distribution via Charge Teleportation

2025-11-06

AI Summary

This work addresses the insufficient robustness of quantum key distribution (QKD) under realistic noise conditions. We propose a novel QKD primitive based on charge teleportation, leveraging entangled many-body ground states—specifically, the transverse-field Ising model with star and one-dimensional chain geometries. By performing local single-qubit operations, Alice directly encodes key bits via control over the local charge sign at Bob’s site, enabling key extraction using single-basis measurements and inherently preserving bit symmetry. Compared to energy teleportation, this scheme exhibits enhanced resilience against local noise and classical bit-flip errors. Combining analytical derivation, exact diagonalization, circuit-based simulation, and proof-of-principle experiments, we quantify the symbol-integrity preservation conditions across multiple system scales. Results demonstrate that although the key generation rate is modest, the protocol maintains high key fidelity under approximately realistic noise—establishing a practical, highly robust QKD pathway suitable for near-term, intermediate-scale quantum hardware.

Technology Category

• Machine Learning: Quantum Machine Learning
• Search and Optimization: Distributed Search
• Intelligent Robots: State Estimation

Application Category

• Security and Privacy: Large-scale security measurements
• Economics, Online Markets and Human Computation: LLM based quality controls for crowd work
• Responsible Web: Data and user privacy-enhancing technologies for the Web

Abstract

We introduce a quantum key distribution (QKD) primitive based on charge teleportation: by Local Operations and Classical Communication (LOCC) on an entangled many-body ground state, Alice's one-bit choice steers the sign of a local charge shift at Bob, which directly encodes the key bit. Relative to energy teleportation schemes, the charge signal is bit-symmetric, measured in a single basis, and markedly more robust to realistic noise and model imperfections. We instantiate the protocol on transverse-field Ising models, star-coupled and one-dimensional chain, obtain closed-form results for two qubits, and for larger systems confirm performance via exact diagonalization, circuit-level simulations, and a proof-of-principle hardware run. We quantify resilience to classical bit flips and local quantum noise, identifying regimes where sign integrity, and hence key correctness, is preserved. These results position charge teleportation as a practical, low-rate QKD primitive compatible with near-term platforms.

Problem

• Develops quantum key distribution using charge teleportation
• Creates robust key encoding via local charge shifts
• Ensures key correctness against noise and imperfections

Innovation

• QKD using charge teleportation with entangled states
• Bit-symmetric charge signal robust to noise
• Protocol implemented on Ising models with hardware validation