IBM agreed to buy a quantum research lab on 23 July. Within days that same lab published, in Nature, a machine that does something the field has been promising for years. It runs itself.
The lab is HRL Laboratories, jointly owned until now by Boeing and General Motors. Its party trick is a quantum processor, the QPU, that no longer needs a room full of instruments babysitting it.
A quick primer. A qubit is the quantum version of a bit. Instead of a plain zero or one it can hold a blend of both, which is where quantum computing gets its power. HRL’s qubits are made of electron spins trapped in silicon, the very same material as ordinary chips. The headline here is not the qubit count, it is who is holding the strings.
A control room on a chip
Normally a quantum chip sits in a fridge near absolute zero while racks of room-temperature electronics outside fire in the control signals down a forest of cables. HRL’s 18-qubit device instead carries its own custom control chip, built in standard CMOS (the bog-standard process behind nearly every computer chip), running right beside it at 4 kelvin, about minus 269 degrees Celsius. The processor runs autonomously, without real-time orders phoned in from the warm world outside.
The kit is built on 200mm isotopically enriched silicon-germanium wafers, a 54-dot array configurable as up to 18 qubits. The error rates are the part that made specialists sit up: single-qubit gate errors around 1.7 in ten thousand, and two-qubit errors as low as 9 in ten thousand in the best runs. That is roughly an order of magnitude better than previous silicon spin efforts of this type.
Why the timing matters
Every quantum outfit eventually hits the same wall: wiring. You cannot run a million-qubit machine if each qubit needs its own cable snaking out of the fridge to a rack upstairs. Moving the control electronics inside the cold, onto the same silicon, is one of the few credible ways past that. Silicon spin qubits are tiny and, in principle, buildable in the same foundries that already stamp out billions of ordinary chips.
Which is why IBM wanted the lab. IBM has bet heavily on a different qubit design, superconducting, and in May announced Anderon, described as the first pure-play quantum wafer foundry. Bolting on HRL’s silicon-spin know-how hedges that bet and feeds the foundry a second technology to manufacture. The deal is expected to close by the end of the third quarter, terms undisclosed, with Boeing and GM staying on as partners.
None of this is a working fault-tolerant computer yet. Eighteen qubits solve nothing useful on their own. But a self-contained, low-error, foundry-made building block is exactly the sort of unglamorous engineering that scaling actually needs.
Did you know: 4 kelvin sounds frigid, and it is, but it is far warmer than the millikelvin temperatures many rival qubits demand, which is precisely what makes running ordinary electronics right next to them possible.