Developing a technology to produce ultra-pure silicon

Physicists from Britain and Australia have developed technology that allows the production of ultra-pure silicon-28, which contains almost no atoms of the other two isotopes.

They are silicon 29 and silicon 30 (less than 0.0002%). Ultra-pure silicon 28 is an ideal material for creating long-lasting qubits and quantum memory cells.

The University of Melbourne press service reported: “This technology paves the way for the development of quantum computers made of silicon, and developing methods for producing extremely pure silicon allows us to begin experiments in which it will be possible to support the long-term operation of a large number of devices.”

David Jamieson, a professor at the University of Melbourne, Australia, said: “A machine with only thirty memory cells will solve many problems faster than all supercomputers.”

It is noteworthy that one of the main obstacles to the development of quantum computers is that increasing the number of interacting qubits leads to a rapid increase in the level of random interference, which disrupts the quantum state of these memory cells and reduces their lifespan. To solve this problem, scientists are working on methods to correct errors and develop long-lasting qubits.

As experts point out, solving the final problem in developing silicon quantum computers is currently hampered by the fact that the lifetime of the qubits inside them depends largely on the purity of the silicon from which these computing devices are made. This is because silicon 28 atoms have ideal quantum properties for the operation of qubits, while silicon 29 and silicon 30 atoms, on the contrary, actively hinder their operation.

British and Australian physicists have developed technology that allows to quickly and with a minimum amount of time and resources increase the number of silicon atoms 28 at a random point on the surface of the chip and reduce the proportions of silicon 29 and silicon 30. To do this, as scientists discovered, it is necessary to irradiate the surface of the material for a sufficiently long time using A beam of silicon 28 ions accelerated using a particle accelerator.

When these ions collide with the silicon surface, they expel the three isotopes of this element from its surface, gradually purifying the material for the overwhelming majority of silicon 29 and silicon 30 atoms. In particular, scientists were able to obtain in a similar way a group of chips with a lower percentage of silicon. 29 about 0.0002%. This is expected to increase the lifetime of qubits by four times, which will allow them to perform complex calculations with their help.