Oxford Ionics develops the most powerful quantum chip
An English start-up presents a chip for quantum computers that controls qubits more precisely than previous systems – and without error correction.
Quantenchip von Oxford Ionics
(Image: Oxford Ionics)
The British start-up Oxford Ionics has developed a new quantum chip that is designed to control qubits with record precision. The chip is based on trapped ions and should be able to be produced on an industrial scale in semiconductor factories. The research team presented their results on the arXiv preprint server.
Quantum computers consist of tiny building blocks known as qubits. To construct stable, high-performance quantum computers, it is necessary to precisely control qubits. There are various approaches to producing qubits, which have different advantages and disadvantages. The Oxford Ionics team relies on ions, i.e. charged atoms, which are held above the surface of a microchip.
High control of individual atoms
The advantage of ionic qubits is their high degree of controllability. Similar to a conventional computer, a quantum computer calculates by performing elementary operations. These operations address either a single qubit or two qubits at the same time. In these cases, we speak of one- or two-qubit gates. To obtain reliable results, the qubits must be precisely controlled, and the quantum gates must be executed with a high degree of precision. "When building a quantum computer, performance is just as important as size," says Oxford Ionics co-founder Tom Harty. "Increasing the qubit number means nothing if the quantum computers don't produce accurate results."
With their latest chip, Oxford Ionics was able to break the industry record for the lowest errors when running one- and two-qubit gates. With up to ten qubits, they achieve a reliability of 99.9992 and 99.97 percent respectively. This means that they have succeeded in doubling the best performance to date. No error correction was carried out. "These results mark a significant advance in ion trap quantum computing and demonstrate the scalability of the technology," says Michael Cuthbert, Director of the UK National Quantum Computing Center.
More qubits thanks to integrated electronics
Scalability has been one of the biggest problems of quantum computers based on trapped ions. Usually, researchers control the ions with lasers. However, the more qubits come together, the more difficult it becomes to target individual qubits with lasers. Oxford Ionics integrates all the electronics for controlling the ions on a silicon chip and does not require a laser.
The ions are trapped and controlled using electric and magnetic fields generated by electrodes on the surface of the microchip. The researchers use tried and tested production techniques from the semiconductor industry and hope to be able to manufacture their chips on a large scale in semiconductor factories in the future. To this end, they are cooperating with the semiconductor manufacturer Infineon from Villach in Austria. The next step is to produce a scalable quantum chip with 256 qubits.
Oxford Ionics was founded in 2019 by English researchers Tom Harty and Chris Ballance. The team currently employs 55 people and has already raised £37 million in investment. Last February, the company was awarded a contract to develop a quantum computer for the UK's National Quantum Computing Center.
(olb)
