IBM achieves sub-15 millikelvin temperatures for quantum processors

IBM has unveiled a modular cryogenic platform that reaches temperatures under 15 millikelvin, making the quantum processor environment colder than the background temperature of space. The apparatus relies on a stacked dilution refrigerator, with each successive plate colder than the one above, culminating in a frigid zone where the qubits operate. Heat from control wires entering from warmer stages can raise the temperature, so minimizing wiring is crucial for scaling up qubit counts.

Other approaches, like QuEra's neutral-atom systems and photonic quantum computers, sidestep the deep-cold requirement by using laser cooling or room-temperature components with only limited cooling for detectors. While current machines host only hundreds to a few thousand qubits, the extreme cooling remains a primary technical hurdle before they can tackle tasks such as drug discovery or breaking current encryption standards. Post-quantum cryptography standards have already been issued by NIST to prepare for future capabilities.