Prototype quantum processor hits record 99.9% qubit fidelity in a major milestone

A Finland-based firm that develops, builds and sells superconducting quantum computers, has achieved significant milestone and showcased improvements in two key metrics characterising the quality of quantum computer.

IQM Quantum Computers achieved a record low error rate for two-qubit operations. It demonstrated a CZ gate between two qubits with (99.91 +- 0.02) % fidelity, which was validated by interleaved randomised benchmarking.

Achieving high two-qubit gate fidelity is the most fundamental and hardest to achieve characteristic of a quantum processor. It’s also essential for generating entangled states between qubits and executing algorithms, according to the company.

Achievement to help develop stable quantum computers

The achievement marks a way toward “fault-tolerant” quantum computing as it achieved record-low error rates in prototype quantum computer. It’s also expected to lead to the development of more stable quantum computers.

IQM maintains that qubit relaxation time T1 of 0.964 +- 0.092 milliseconds and dephasing time T2 echo of 1.155 +- 0.188 milliseconds was demonstrated on a planar transmon qubit on a silicon chip fabricated in IQM´s own fabrication facilities.

The coherence times, characterized by the relaxation time T1 and the dephasing time T2 echo, are among the key metrics for assessing the performance of a single qubit, as they indicate how long quantum information can be stored in a physical qubit, according to the company.

IQM’s fabrication technology has matured

“These major results show that IQM’s fabrication technology has matured and is ready to support the next generation of IQM’s high-performance quantum processors,” said IQM in a press release .

“The results follow IQM´s recent benchmark announcements and indicate significant potential for further advancements on gate fidelities essential for fault-tolerant quantum computing and processors with higher qubit counts.”

High fidelity in two-qubit gates are key for generating entangled states — when qubits become interconnected in such a way that the state of one directly affects the state of the other, regardless of the distance between them. Quantum entanglement is a cornerstone of quantum mechanics, what Einstein dubbed “spooky action at a distance”, reported Live Science .

Achievement cements IQM’s tech leadership

‍”This achievement cements our tech leadership in the industry. Our quantum processor quality is world-class, and these results show that we have a good opportunity of going beyond that,” said Dr. Juha Hassel, the Vice President of Engineering at IQM Quantum Computers.

‍Hassel claims that IQM is on track with its technology roadmap and is actively exploring potential use cases in machine learning, cybersecurity, route optimization, sensor simulation, chemistry, and pharmaceutical research.

The improvements made in the two characteristics, two-qubit gate fidelity and coherence time, allow the quantum computer to be developed for more complex use cases, according to the company. The significance of these results stems from the fact that only very few organizations have achieved comparable performance numbers before, according to the company.