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ETH Zurich physicists have demonstrated a way to turn imperfect random inputs into random bits certified by a quantum experiment. The team connected two superconducting quantum chips through a 30-metre refrigerated link and combined a loophole-free Bell test with a randomness-extraction algorithm. The result addresses a weakness in cryptography: apparently random inputs can contain correlations that make secret keys predictable.

The experiment demonstrates randomness amplification, a task that cannot be achieved using classical processing alone under the same assumptions. Its certification comes from the measured quantum correlations rather than trust in the devices' internal construction. The present apparatus requires cryogenic hardware and a long physical separation between the chips; turning the result into a practical randomness service remains a further engineering step.

NIST published its first three final post-quantum cryptography standards, including two developed by IBM Research scientists in Zurich with external collaborators. ML-KEM, derived from CRYSTALS-Kyber, provides a mechanism for establishing shared secrets. ML-DSA, derived from CRYSTALS-Dilithium, provides digital signatures. Their standardisation turned years of cryptographic research and public evaluation into specifications ready for deployment.

The standards address the risk that future quantum computers could break widely used public-key cryptography. They run on conventional computers and give software developers concrete specifications for migrating communication and authentication systems. NIST's third standard, SLH-DSA, is based on hash-based signatures and was co-developed by a researcher who subsequently joined IBM. The publication provides a common foundation for replacing vulnerable cryptographic components across enterprise and public infrastructure.