IBM made two "critical" advances that bring us closer to the creation of an ultra-fast quantum computer.
The researchers demonstrated the ability to detect and measure both types of quantum errors (bit-flip and phase-flip) at the same time. They also revealed a new square quantum bit circuit design that could successfully scale to much larger dimensions.
The new quantum bit circuit is based on a square lattice of four superconducting qubits. Its square shape, as opposed to a linear array, allows both errors to be detected simultaneously and has the best potential to be incorporated into a working-size quantum system to date.
"Quantum computing could be potentially transformative, enabling us to solve problems that are impossible or impractical to solve today," said Arvind Krishna, senior vice president and director of IBM Research. "While quantum computers have traditionally been explored for cryptography, one area we find very compelling is the potential for practical quantum systems to solve problems in physics and quantum chemistry that are unsolvable today. This could have enormous potential in materials or drug design, opening up a new realm of applications."
Quantum computing could lead to the development of new materials and drug compounds without the need for costly trial and error lab experiments. They could also quickly sort huge databases and store a staggering amount of data.
One of the largest roadblocks in the realization of the quantum computer has been the inability to find a way to control or eliminate quantum decoherence, which is the creation of errors in calculations caused by factors such as heat and material defects.
"Up until now, researchers have been able to detect bit-flip or phase-flip quantum errors, but never the two together. Previous work in this area, using linear arrangements, only looked at bit-flip errors offering incomplete information on the quantum state of a system and making them inadequate for a quantum computer," said Jay Gambetta, a manager in the IBM Quantum Computing Group. "Our four qubit results take us past this hurdle by detecting both types of quantum errors and can be scalable to larger systems, as the qubits are arranged in a square lattice as opposed to a linear array."
The findings were published in a recent edition of the journal Nature Communications.