Quantum Computing

Computers that exploit superposition and entanglement to solve certain problems far faster than classical machines. The field has demonstrated 'supremacy' on contrived tasks and is now racing toward error-corrected machines capable of useful work.

A fault-tolerant quantum computer would transform chemistry, materials science and cryptography. The timeline determines how urgently institutions must prepare — especially for the cryptographic transition.

Multiple hardware platforms compete. Error-correction milestones — logical qubits with error rates that improve as the code grows — have been demonstrated. Useful, fault-tolerant machines remain years away by most credible estimates.

Hardware companies and labs

Superconducting, trapped-ion, neutral-atom and photonic platforms.

Standards bodies

Post-quantum cryptography migration.

Chemistry and materials groups

The first credible applications.

1. 2019

   Quantum supremacy demonstration on a sampling task

2. 2024

   Error correction below the surface-code threshold

• Recent

  Error-corrected demonstrations extend to longer computations

  See The Signal.

Physical qubits of several kinds; surface and other error-correcting codes; cryogenics and control electronics; quantum algorithms for simulation and optimisation.

• Quantum supremacy using a programmable superconducting processor, Nature (2019)
• Quantum error correction below the surface code threshold, Nature (2024)

1. 01Which platform scales?
2. 02What is the first commercially valuable computation?
3. 03How fast must cryptography migrate?

Error correction has moved from theory to demonstration, making scaling the central engineering question.

Logical-qubit counts, error rates versus code size, and post-quantum cryptography deployment.

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