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.
Intel has passed a key milestone while running alongside Google and IBM in the marathon to build quantum computing systems. The tech giant has unveiled a superconducting quantum test chip with 49 qubits: enough qubits to possibly enable quantum computing that begins to exceed the practical limits of modern classical computers.
Despite the hype and hoopla surrounding the burgeoning field of quantum computing, the technology is still in its infancy. Just a few years ago, researchers were making headlines with rudimentary machines that housed less than a dozen qubits -- the quantum version of a classical computer's binary bit. At IBM's inaugural Index Developer Conference held in San Francisco this week, the company showed off its latest prototype: a quantum computing rig housing 50 qubits, one of the most advanced machines currently in existence.