Silicon’s New Quantum Frontier
Silicon powered classical computing for decades. Now silicon is showing promise as a foundation for practical quantum processors. Researchers at UNSW and spin-out Silicon Quantum Computing have developed the 14|15 platform, which places phosphorus atom spin qubits inside a silicon substrate to combine atomic-scale quantum control with industry-standard materials.
The 14|15 Platform: High-Performance Qubits
The 14|15 approach uses single phosphorus donor atoms as spin qubits embedded in isotopically purified silicon. These spin qubits benefit from low magnetic noise and long coherence times, because silicon-28 reduces decoherence sources. Lab results report high-fidelity single- and two-qubit gates and low error rates for entangled Bell states, a key benchmark for quantum logic.
How Qubits Are Created and Managed
Each qubit is the quantum spin of an electron bound to a phosphorus atom. Control occurs with local electromagnetic gates and microwave pulses. Two-qubit operations exploit the electron-exchange interaction so neighboring spins can become entangled on demand. Readout uses sensitive charge and spin-sensing techniques tuned to silicon device architecture.
Addressing Quantum Scalability
Scaling beyond tens of qubits is the central engineering hurdle. The 14|15 platform proposes a modular route: arrays of donor qubits can be manufactured with techniques compatible with CMOS foundries, then linked using controlled exchange interactions or intermediary electron shuttling between registers. This makes it easier to plan larger qubit arrays while keeping error rates low through material purity and optimized gate designs.
Implications for Quantum’s Future
Silicon-based qubits bring practical benefits: long coherence, compatibility with semiconductor fabrication, and demonstrated high-fidelity entanglement for Bell states. For quantum AI and commercial systems, that translates to hardware that can be scaled and integrated with existing supply chains. The 14|15 platform is not a final product, but it marks a concrete step toward robust, scalable quantum processors that can support real-world quantum algorithms.
