Google is maintaining its edge in the world of quantum computing.
Its 20-qubit processor is currently undergoing tests, and the company appears to be on schedule to have its working 49-qubit chip ready by the end of 2017 as promised. Until it began trialing the 20-qubit chip, Google’s most powerful quantum chip was the 9-qubit effort from 2015.
Traditional computer bits are binary, only existing as either 0 or 1; they’re like light switches that are either on or off.
Qubits, on the other hand, can be 0 or 1 like regular bits, but can also have quantum properties that allow them to exist in a superposition where they are both 0 and 1 simultaneously.
This makes qubits potentially far more powerful, because instead of figuring something out by trying each option one by one, they can simultaneously compute more than one possibility.
Google’s 49-qubit chip will allow them to develop a 49-qubit quantum system that can solve problems that are far beyond the capacity of ordinary computers: Google calls this goal quantum supremacy. The 20-qubit system that the Google quantum computing team is now working on currently boasts a “two-qubit fidelity” of 99.5 percent.
The higher the rating, the fewer errors the system makes. Quantum supremacy demands not only a 49-qubit system, but also sufficient accuracy to achieve a two-qubit fidelity of at least 99.7 percent—which Google is on track to deliver by the end of 2017.