IBM's quantum computer reaches 50-qubit milestone

Part of the cooling system used in IBM's 50-qubit quantum computer. Photo: IBM Research / Flick

IBM announced on Friday it has built a prototype 50 quantum bit (qubit) computer — the number some researchers think is needed to establish "quantum supremacy" over traditional computers. The company said its cloud computing platform will also be upgrading to a 20-qubit computer by the end of 2017.

Why it matters: Today's supercomputers are on processing par with quantum computers operating with less than 50 qubits. But quantum processors with more than 50 quantum bits are thought to be able to perform simulations and calculations that traditional computers cannot. IBM's previous version used 17 qubits.

How it works: Standard computers store information as a 0 or a 1. Quantum versions can represent it as 0, 1 or both at the same time, which gives them more processing power that could be useful for particular types of calculations.

Yes, but: It isn't ready for practical use. The quantum state lasts a mere 90 microseconds. And, the University of Maryland's Andrew Childs tells MIT Technology Review, it isn't just about the quantity of qubits but also quality. "Those qubits might be noisy, and there could be issues with how well connected they are."

Keep in mind: Quantum computers are well-suited for solving some problems — simulating chemical interactions at the subatomic level or optimizing supply chains, for example — but not necessarily everyday tasks.

Other players: Google, Intel, and a company called Rigetti are all working on quantum computing.