Researchers from Japan have developed a new method for making 5-centimeter diamond plates that can be used for quantum computing. Diamond’s properties allow you to store a staggering amount of data, equivalent to one billion Blu-Ray discs.

Diamond is one of the most promising materials for practical quantum computing systems, including memory. A special defect in the crystal known as the nitrogen vacancy center can be exploited to store data in the form of superconducting quantum bits (qubits), but too much nitrogen in diamond impairs its quantum storage capacity.

This meant that a compromise had to be found – scientists had to create either large diamond plates containing too much nitrogen, or ultrapure diamond plates too small to be useful for data storage. But now researchers from Saga University and Japanese company Adamant Namiki Precision Jewelery Co. developed a new method for producing ultrapure diamond plates large enough for practical use.

With the new method, the resulting diamond slabs are 5 cm in diameter and have such a large data density that they could theoretically store the equivalent of one billion Blu-Ray discs, according to the team. A Blu-Ray disc can store up to 25GB (provided it’s single layer), which means this diamond platter can store a massive 25 exabytes of data. The company calls these plates Kenzan Diamond.