This Diamond’s Flaw Is the Whole Point: It Can Hold a Qubit

For a jeweler, a diamond’s imperfections can be a problem. For a quantum engineer, the right imperfection can be the useful part. Researchers deliberately work with tiny defects in diamond that provide quantum states they can control, turning an otherwise unlikely material into a computing building block.

One example is a nitrogen-vacancy center. NIST explains that it combines a nitrogen atom replacing a carbon atom with an empty neighboring site where another carbon should be. The defect’s electron spin has distinct quantum energy states that can be manipulated with light and microwaves.

Some diamond computing hardware can even work without a giant cryogenic fridge. Fraunhofer reported installing Quantum Brilliance’s diamond-based accelerator in May 2025, in a standard server rack alongside conventional computing hardware. It uses nitrogen-vacancy centers and was introduced as a platform for research and hybrid quantum-classical algorithms.

But diamond does not automatically mean room temperature. A September 9, 2026 QuTech announcement describes a different prototype using tin-vacancy centers, operating at about 1.55 kelvin, or minus 271.6 degrees Celsius. It combines a diamond spin system with tiny optical components designed to guide emitted photons.

That prototype contains one module; it has not yet demonstrated optical connections between multiple computing modules. The proposed payoff is eventually linking separate quantum processors with light. Both examples show why diamond defects attract researchers, while useful scale and computing performance still depend on much more than choosing a remarkable material.