At the American Physical Society conference in early March, Google announced their Bristlecone chip was in testing. This is their latest quantum computer chip which ups the game from 9 qubits in their previous test chip to 72 — quite the leap. This also trounces IBM and Intel who have 50- and 49-qubit devices. You can read more technical details on the Google Research Blog.
It turns out that just the number of qubits isn’t the entire problem, though. Having qubits that last longer is important and low-noise qubits help because the higher the noise figure, the more likely you will need redundant qubits to get a reliable answer. That’s fine, but it does leave fewer qubits for working your problem.
The previous Google device had a low error rate and the new chip uses the same topology. Google hopes to demonstrate similarly low error rates on it, too. You can see a graphical representation of the layout in the right-hand side of the graphic at the top of this post.
This is the latest in the race to reach what is known as quantum supremacy. Quantum computing simulators exist that compute state information for all possible states of a multi-qubit system (something a quantum computer does naturally). That works, but at about 50 qubits, the computation and memory load is too great for modern conventional computers. That means a successful quantum computer in that range could solve certain kinds of problems that modern computers can’t, and everyone wants to be the first to demonstrate this.