Given all the buzz, you might be surprised you don’t have your very own quantum computer yet. The field of quantum computing — in which a processor handles a range of inputs and outputs at once — has pushed new bounds over the last few years. But quantum computers are still largely used for research. For users, the day in which quantum computers are ubiquitous, or even useful, has yet to arrive.
We still aren’t there yet. But today, we get a step closer — Google unveiled Bristlecone, its latest quantum processor, and its most powerful to date.
Here’s what you need to know about Bristlecone.
Qubits, or quantum bits, are the basic units of information in a quantum processor. The more qubits a processor has, the more information it can process at once, and the more powerful it is overall.
IBM recently produced a 50-qubit system. But the Bristlecone trumps it with a whopping 72 qubits.
The various companies pursuing quantum hardware are always keen to brag about how many qubits their latest system possesses, and though that’s not the deciding factor of a quantum processor’s functionality, it’s definitely important.
In spite of recent advances, today’s qubits are still unstable, and hardware needs to be sturdy to run them. Quantum computers need to keep their processors extremely cold and protect them from external shocks. Even accidental sounds can cause the computer to make mistakes.
To operate in even remotely real-world settings, quantum processors need to have an error rate of less than 0.5 percent for every two qubits. Google’s best has be 0.6 percent using its much smaller 9-qubit hardware. The blog post didn’t state Bristlecone’s error rate, but Google has made it clear that the company strives to improve upon its previous results. To drop the error rate for its high-qubit processor, engineers need to figure out how software, control electronics, and the processor itself can work alongside one another without causing errors.
Researchers are working so hard to bring us quantum computers because they believe the devices will inevitably outperform classical supercomputers. The term “quantum supremacy” refers to the prospect of a quantum computer solving a problem that a classical system cannot. Some researchers suspect this could happen when quantum computers reach 100 qubits. When it does happen, quantum supremacy will be a “watershed moment” for the field, according to Google’s blog post on Bristlecone.
Bristlecone doesn’t quite get us there. But the Google team is “cautiously optimistic” that the new processor could hasten the process. And the result will mean quantum computers could then become “functionally useful,” The Next Web writes.