Despite global efforts by leading universities and top hi-tech corps, including Google, IBM, and Microsoft, to try upscale quantum technology and produce a real-world quantum PC, they’ve been unable to overcome the huge tech issue of how to achieve calculations within a tolerable margin of error.
However, a theoretical discovery by Sydney University Nano Institute physicists — Prof. Stephen Bartlett, Associate Professor Steven Flammia, and David Tuckett — of what they’ve termed a ‘quantum hack,’ might make allowance for massive efficacy advances in the tech of quantum computing.
At the essence of Quantum technologies are qubits (quantum bits), which are disposed to intrusions from their contiguous environs, causing them to lose lucidity as well as their quantum assets. Catering for this via error rectification is fundamental to the effective growth of quantum technologies.
The quantum team’s breakthrough, published in the famed Physical Review Letters journal, accommodates a 400% increase in the volume of noise interference a quantum computer-driven system can sustain in theory while maintaining its reliability. According to Flammia, this was accomplished by modifying their “quantum decoder to equal the properties of the noise experienced by the qubits.” They are, so to speak, ‘hacking’ the error correction coding usually accepted.
At this time the unwritten rule for the quantum reliability threshold in a qubit architecture is around 1%, meaning that no less than 99% of the qubits in a system need to maintain data and reliability for certain amounts of time to achieve any worthwhile computations. The actual 1% threshold stems from a hypothetical viewpoint wherein idyllic hardware ought to accommodate a 10.9% error limit. The tolerance drop is from ‘noise’ that occurs when using computers in actuality.
Supposing model hardware, the team’s work has a threshold for error correction equal to 43.7% — a quadruple upgrade to the existing hypothetical foundation for error correction. In other words, less actual quantum bits may be needed for a rudimentary quantum circuit to make a useful computation.
This innovative methodology ought to be relevant for every quantum system regardless if the qubits depend on trapped ions, topological structures, superconductors, or semiconductors. The next step is for scientists to use ‘noisy’ hardware to test if this ‘quantum hack’ works on actual systems.