Entropy diagnostics for cryptographic key material from random circuit sampling

Title

Entropy diagnostics for cryptographic key material from random circuit sampling

Creator

Sebastian, Eby; Poonia, Ramesh Chandra

Description

Random Circuit Sampling (RCS) has emerged as a leading paradigm for demonstrating quantum advantage. Beyond computational complexity, RCS provides a high-dimensional, chaotic probability distribution whose structure is characteristic of random unitary dynamics; here, we study its entropy properties in an ideal statevector baseline intended for later hardware validation. In this work, we present a reproducible validation framework for certifying cryptographic keys using a 12-qubit RCS ensemble (N = 4096 states ) within an ideal quantum simulation framework. Unlike standard Quantum Random Number Generators (QRNGs), which often rely on single-qubit optics, our protocol utilises multi-qubit entanglement to ensure nonlocality. We quantify the security of the system using a dual-metric approach: basis-dependent Min-Entropy (H? ? 9.05 bits ) for cryptographic extractability, and basis-independent Subsystem Von Neumann Entropy (S ? 3.96 bits) for quantum certification. We further demonstrate a privacy-amplification pipeline that uses a frequency-preserving, endian-corrected SHA-3 extraction to produce a 256-bit secure key (candidate key material). This study provides a transparent methodological bridge between the theoretical Quantum Supremacy regime and practical cryptographic key generation. 2026, Taru Publications. All rights reserved.

Source

Journal of Discrete Mathematical Sciences and Cryptography;Volume;29;Issue;2;pp.1023-1032

Date

01-01-2026

Publisher

Taru Publications

Subject

Entropic certification; Min-entropy; Privacy amplification; Quantum cryptography; Quantum entanglement; Quantum random number generation (QRNG); Random circuit sampling (RCS)

Coverage

Sebastian E., Department of Computer Science, CHRIST (Deemed to be University), Karnataka, Bangalore, 560029, India; Poonia R.C., Department of Computer Science, CHRIST (Deemed to be University), Karnataka, Bangalore, 560029, India

Rights

Restricted Access; Hardcopy may be available in the library

Relation

ISSN: 9720529;

Format

online

Language

English

Type

Article

Identifier

https://doi.org/10.47974/JDMSC-2641

https://www.scopus.com/pages/publications/105031570406?origin=resultslist