As the technological progress codified as Moore's Law slows down, computer scientists are turning to alternative methods of computing, such as superconducting quantum processors to deliver computing gains in the future. Jeffrey Welser, vice president and lab director at IBM Research at Almaden, spoke about quantum computing at the 49th annual Semicon West chip manufacturing show in San Francisco last week. I caught up with him to get his take on quantum computing for the layperson. IBM also displayed a part of its IBM Q System at the show, giving us an idea of how much refrigeration technology has to be built around a current quantum processor to ensure its calculations are accurate. Binary digits -- ones and zeroes -- are the basic components of information in classical computers. Quantum bits, or qubits, are built on a much smaller scale.
Intel Labs unveiled a first-of-its-kind cryogenic control chip -- code-named "Horse Ridge" -- that will speed up development of full-stack quantum computing systems. Horse Ridge will enable control of multiple quantum bits (qubits) and set a clear path toward scaling larger systems -- a major milestone on the path to quantum practicality. Developed together with Intel's research collaborators at QuTech, a partnership between TU Delft and TNO (Netherlands Organization for Applied Scientific Research), Horse Ridge is fabricated using Intel's 22nm FinFET Low Power (22FFL) technology. In-house fabrication of these control chips at Intel will dramatically accelerate the company's ability to design, test and optimize a commercially viable quantum computer. Jim Clarke, Intel's director of quantum hardware, says this integration is possible because of the kind of qubits the company uses.
Quantum computing is heating up. For the first time, quantum computer chips have been operated at a temperature above -272 C, or 1 kelvin. That may still seem frigid, but it is just warm enough to potentially enable a huge leap in the capabilities. Quantum computers are made of quantum bits, or qubits, which can be made in several different ways. One that is receiving attention from some of the field's big players consists of electrons on a silicon chip.
One of the big limiters to today's quantum computing systems is that while their superconducting qubits live in a cryogenic enclosure at less than 1 kelvin, all the control and readout circuits must be at room temperature. For today's sub-100-qubit systems, there's enough space for specialized RF cabling to come in and out of the enclosure. But to scale up to the million-qubit systems needed to do really cool stuff, there just won't be enough room. So quantum computer engineers want to bring some of those electronics inside the cryogenic fridge. In a first step, researchers at Google, the University of Massachusetts at Amherst, and the University of California Santa Barbara reported making a key control circuit in CMOS that will work at cryogenic temperatures.