Future quantum computers will be capable of doing computations that are now inconceivable even for the most powerful supercomputers. However, there are numerous obstacles to overcome before getting there. Error-correcting is one of them. For the first time, researchers at ETH Zurich have demonstrated that it is feasible to automatically repair faults in quantum systems and that this can do in such a fast and continuous manner that the outputs of quantum operations may be utilized in practice. The findings have been submitted to the ArXiv repository for peer review.
In a statement, co-author Andreas Wallraff, Director of the Quantum Center at ETH Zurich, stated, “The proof that faults in a quantum computer operating with quantum bits (qubits) can be rectified fast and frequently is a breakthrough on the way to developing a viable quantum computer.”
Because these new computers are based on quantum systems, their processor units must be kept at extremely low temperatures, just above absolute zero. Procedures for dealing with mistakes are scrutinized. The apparatus investigated in this study has 17 qubits and runs at a temperature of 0.01 Kelvin. That’s a tenth of a degree higher than absolute zero.
The qubits are superconducting at that temperature, meaning electricity flows through them with no resistance. Nine of the 17 qubits are arranged in a three-by-three lattice on a square array. They are the logical unit of the system. These nine components do all of the calculations. The remaining eight act as a control and are responsible for detecting system problems. The system can then fix itself if the qubits notice them. Disturbances that modify the information in the system can be identified and accounted for using these.
“Right now, we’re not directly rectifying the faults in the qubits,” co-lead author Sebastian Krinner noted. “However, for the vast majority of arithmetic operations, that isn’t even essential.”
This new study demonstrates that error correction is doable and practical, but we are still a long way from quantum computers being fault-proof. The scientists noted in their study, “Our demonstration of repetitive, rapid, and high-performance quantum error correction cycles, together with recent developments in ion traps, reinforces our notion that fault-tolerant quantum computation will be realistically realizable.”
Work is not the sole method for dealing with error rectification. A new quantum phase has recently been proposed as a potential solution to this problem. Quantum computers may not yet exist, but when new issues arise, scientists all across the world rise to the occasion.
