Quantum competitors bristle as Google (finally) unveils 72-qubit processor

Dive Brief:

After weeks of the industry bating its breath, Google finally dropped quantum news Monday with a preview of Bristlecone, the company's new 72-qubit processor. Bristlecone follows the same underlying physics and coupling, control and readout schemes seen in Google's existing 9-qubit processor but is scaled to a 72-qubit square array.
Bristlecone will serve as a testing ground for the scalability of Google's qubit technology, improvements on system error rates and ML, simulation and optimization applications.
Google believes the Bristlecone proof of concept will provide the building blocks for larger quantum computing capabilties. "We are cautiously optimistic that quantum supremacy can be achieved with Bristlecone," wrote Julian Kelly, research scientist at Google's Quantum AI Lab, in a blog post.

Dive Insight:

IBM made a 20-qubit processor available to clients in 2017 with plans to bring its 50-qubit prototype to next generation systems, and Intel rolled out a 49-qubit quantum test chip in January. But, just like Google's, these systems are still far from hitting quantum supremacy.

Creating a stable processor with more qubits in every iteration is no easy feat, but it's not the only thing quantum researchers have to worry about. These processors also need a low enough error rate and computational length to outperform classical computing systems.

A low error rate and sufficient number of qubits are both necessary to achieve quantum supremacy.

Google Research Blog

Google believes that a quantum processor with 49 qubits, a two-qubit error rate below 0.5% and a circuit depth greater than 40 should be enough to "comfortably" reach quantum supremacy.

Speculation is swirling around when Microsoft will make a quantum computing announcement of its own. Alibaba, looking to grow its presence in the global cloud and quantum markets, announced an 11-qubit quantum processor available through its cloud platform last week.

Whether the American tech giants can win the quantum race remains to be seen. China dominates quantum research worldwide and is inciting fear and uncertainty in many American lawmakers and researchers. Whichever company or country hits the milestone first will be at a major strategic and digital security advantage.