Practical Quantum Public Key Encryption for Noisy Intermediate-Scale Quantum Devices → Research

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Briefing

This research addresses the critical problem of deploying quantum public key encryption (Q-PKE) on current noisy intermediate-scale quantum (NISQ) devices, a challenge previous Q-PKE schemes failed to meet due to their high qubit coherence demands. The foundational breakthrough is a novel Q-PKE scheme featuring quantum-classical public keys and classical ciphertexts, engineered for noise resilience and minimal qubit requirements. This innovation has the profound implication of enabling secure cryptographic systems to leverage quantum mechanics on existing hardware, thereby unlocking the potential for novel quantum-native applications in the immediate future of blockchain architecture and security.

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Context

Public Key Encryption (PKE) is a cornerstone of secure communication, with classical implementations relying on computational hardness assumptions vulnerable to quantum attacks. Quantum PKE (Q-PKE) offers an alternative, yet prior schemes demanded extensive coherent qubits. This requirement rendered them impractical for current Noisy Intermediate-Scale Quantum (NISQ) hardware, thus preventing the deployment of quantum-native cryptographic primitives on existing quantum computers.

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Analysis

The paper introduces a novel quantum Public Key Encryption (PKE) scheme specifically designed for Noisy Intermediate-Scale Quantum (NISQ) devices. The foundational concept centers on a hybrid key structure, where the public key is quantum-classical and the ciphertext remains classical. This design directly addresses NISQ device limitations by minimizing the required coherently acting qubits and integrating noise resilience. The scheme achieves practical implementability by judiciously balancing quantum and classical components, enabling operation within current hardware constraints.

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Parameters

Core Concept → Quantum Public Key Encryption
New System/Protocol → Practical Quantum PKE for NISQ
Key Authors → Nishant Rodrigues, Walter O. Krawec, Brad Lackey, Deb Mukhopadhyay, Bing Wang
Key Feature 1 → Quantum-classical public keys
Key Feature 2 → Classical ciphertexts
Key Constraint → NISQ devices
Security Basis → Quantum-secure cryptographic assumptions
Resilience → Noise-resilient
Qubit Requirement → Small number of qubits
Submission Date → September 22, 2025

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Outlook

This research paves the way for deploying quantum-native cryptographic primitives on existing, albeit noisy, quantum hardware. Future work could explore optimizing the quantum-classical key generation, investigating the scheme’s robustness against evolving NISQ device noise models, or extending the design to other quantum cryptographic primitives. Potential real-world applications include secure communication channels leveraging quantum properties, enabling early-stage quantum internet security, and exploring novel cryptographic protocols that are impossible with classical information alone within the next 3-5 years.

This research decisively advances the feasibility of quantum-native cryptographic security on contemporary quantum hardware, establishing a critical bridge towards post-quantum secure communication.

Signal Acquired from → arxiv.org