IBM will sell 50-qubit universal quantum computer “in the next few years”

IBM will build and sell commercial 50-qubit universal quantum computers, dubbed IBM Q, “in the next few years.” No word on pricing just yet, but I wouldn’t expect much change from $15 million—the cost of a non-universal D-Wave quantum computer.

In other news, IBM has also opened up an API (sample code available on Github) that gives developers easier access to the five-qubit quantum computer currently connected to the IBM cloud. Later in the year IBM will release a full SDK, further simplifying the process of building quantum software.

You can’t actually do much useful computation with five qubits, mind you, but fortunately IBM also has news there: the company’s quantum simulator can now simulate up to 20 qubits. The idea is that developers should start thinking about potential 20-qubit quantum scenarios now, so they’re ready to be deployed when IBM builds the actual hardware.

Speaking of hardware, it seems IBM has accelerated its universal quantum computing roadmap somewhat. In May last year IBM said it would like to build a 50-qubit computer “in the next decade.” Now we’re down to “the next few years.”

IBM has also fleshed out its quantum computing roadmap a little, providing some guidance on how it will actually build a universal 50-qubit computer:

IBM’s roadmap to scale to practical quantum computers is based on a holistic approach to advancing all parts of the system. IBM will leverage its deep expertise in superconducting qubits, complex high performance system integration, and scalable nanofabrication processes from the semiconductor industry to help advance the quantum mechanical capabilities.

Despite the aggressive roadmap, however, there is no evidence that any scaling has, in fact, occurred. Recal the original publication, which involved nine computational qubits, and a total of 1000 qubits. Now IBM wants their quantum computer to be fully interconnected, so 50 computational qubits requires 1,225 connections. Each link seems to require 48 qubits for control, so 58,800 qubits. This is quite a jump for 1000 qubits on a board.

Comparing to D-Wave, which also produces boards with around 1000 qubits, they always end up with one or two non-functional qubits. In this case, it is most likely that a non-functional qubit will be in the connection between two computational qubits, rendering not one, but two nodes useless.

We’ll be a lot more confident in IBM’s scaling when we see actual papers with increasing numbers of computational qubits.

Other than D-Wave, IBM doesn’t have much competition in the quantum computing space—and as we’ve explained in the past, both companies appear to be approaching quantum computing quite differently. IBM has set its sights on building a true universal quantum computer, which can be used to solve any quantum algorithm under the sun. D-Wave seems more focused on scaling up the number of qubits and ensuring its system can integrate easily with classical computers, but not ensuring its qubits are actually qubits.

Me, looking young and amazed next to a dilution refrigeration unit. Credit: Sebastian Anthony

While exact pricing, availability, and specs are still a long way off, it’s fairly safe to assume that IBM’s quantum computers will be about the same price as a D-Wave (~$15 million) or perhaps a little dearer. Both systems are fundamentally the same thing: a fancy chip inside a box that contains a multi-stage dilution refrigerator from a company like BlueFors.

Dilution refrigerators take about 24 hours to cool down, but they can then keep the chip at close-to-absolute-zero (~5mK, -273.145°C)—a prerequisite for current quantum computing chips—almost indefinitely.

And finally, a random factoid: the photo on the right shows me standing on a ladder next to one of IBM’s dilution refrigerators at IBM Research headquarters in upstate New York back in 2013.

Additional reporting by Chris Lee

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