A team of US mathematicians and physicists has found a way to overcome the limitations of topological quantum computing by exploiting a previously neglected aspect of topological quantum field theory. The discovery opens up new possibilities for anyon-based quantum computing, which uses particle-like knots in materials to perform calculations.
Currently, topological quantum computers rely on “anyons” that can only be manipulated through braiding, but certain anyons have a “quantum dimension of zero,” making them useless for computation. However, the team has discovered new mathematical tools that allow these anyons to be used despite their limitations.
The breakthrough involves adding back into the model “neglectons,” which were previously neglected, and finding ways to confine computational space to areas where anyon transformations work out as unitary. This solution solves a problem of non-unitarity in quantum mechanics.
Experts praise the discovery as a substantial theoretical advance with important implications for overcoming limitations of semisimple models. However, experimental realization of this progress is still a long-term goal. The team’s leader, Aaron Lauda, notes that there are precedents for particles being discovered after mathematical predictions, and suggests that researchers should look for “neglectons” in existing systems to further advance the field.
Source: https://physicsworld.com/a/predicted-quasiparticles-called-neglectons-hold-promise-for-robust-universal-quantum-computing