Intel has issued a statement reiterating that they are working with Netherlands-based QuTech on spin qubit (also known as quantum dot) technology. This technology makes a lot of sense for Intel because these qubits can have a much smaller cell size, better coherence times, easier cooling requirements, and more similarities to standard semiconductor manufacturing than the alternative superconducting technology. Intel also revealed that it has developed a process flow for these qubits that can run in one of its regular 300 mm semiconductor fabs and they intend on shortly producing many wafers and thousands of small qubit arrays per week.
The fact that Intel and QuTech had been working on spin qubit technology has been mentioned before. (See our report of June 30, 2016 where we reported on some of their early research in this area.) So it was actually a surprise to us when Intel announced last year that it had developed 17 and 49 qubit chips based upon superconducting technology. Our belief is that Intel will be pursuing spin qubits as its long term technology and that the superconducting chips were interim chips to help Intel and QuTech move ahead on other areas of the platform including control electronics, cooling, packaging, and software. Also, note that Silicon Quantum Computing in Australia is also pursuing spin qubits for similar reasons as Intel has stated.
In conjunction with Intel’s statement they also disclosed that their partner QuTech had developed a programmable two-qubit processor with the University of Wisconsin based upon spin qubit technology and just published a paper in Nature describing it. Apparently, the actual processing of that chip was performed at the University of Wisconsin, but presumably aspects of that design will be used by Intel for their future spin qubit development.
One additional question is what is Intel planning to do regarding quantum software. There is a similar group in the Netherlands called QuSoft that complements QuTech and is focusing on quantum software. At this point, there is no sign that Intel is partnering with them, but perhaps they will choose to work with them or some other software group once their quantum hardware gets further along.