A University of Washington-led team has made a key quantum computing breakthrough by detecting fractional quantum anomalous Hall states in semiconductor material flakes, which could be instrumental in creating stable, fault-tolerant qubits.

Quantum computing could revolutionize our world. For specific and crucial tasks, it promises to be exponentially faster than the zero-or-one binary technology that underlies today’s machines, from supercomputers in laboratories to smartphones in our pockets. But developing quantum computers hinges on building a stable network of qubits — or quantum bits — to store information, access it and perform computations.

Yet the qubit platforms unveiled to date have a common problem: They tend to be delicate and vulnerable to outside disturbances. Even a stray photon can cause trouble. Developing fault-tolerant qubits — which would be immune to external perturbations — could be the ultimate solution to this challenge.

A team led by scientists and engineers at the University of Washington has announced a significant advancement in this quest. In a pair of papers published on June 14 in Nature and June 22 in Science, they report that, in experiments with flakes of semiconductor materials — each only a single layer of atoms thick — they detected signatures of “fractional quantum anomalous Hall” (FQAH) states. The team’s discoveries mark a first and promising step in constructing a type of fault-tolerant qubit because FQAH states can host anyons — strange “quasiparticles” that have only a fraction of an electron’s charge. Some types of anyons can be used to make what are called “topologically protected” qubits, which are stable against any small, local disturbances.

To read more, click here.