Fermilab

What Is a Dilution Fridge?

The video introduces dilution refrigerators—special cryogenic systems that reach temperatures as low as 10 millikelvin, colder than outer space—and highlights Fermilab’s world‑renowned expertise in building and operating them for quantum‑technology research. The apparatus cools in stages: ~50 K, then 3 K, 1 K, 0.1 K, finally the base 10 mK mixing chamber. Gold‑plated components are used for their 1‑2 % emissivity, minimizing radiative heat. Experiments are thermally anchored to the mixing‑chamber plates to ensure uniform cooling, and the refrigerators typically run uninterrupted for one to twelve months, though power or cooling‑water failures halt quantum experiments. Chris James, an ultra‑low‑temperature engineer, and physicist Daniel Bafia explain that the refrigerator is not a quantum computer itself but the essential platform that enables qubits to operate. They showcase a 10 mK cavity experiment and discuss plans to leverage Fermilab’s 4 K cryogenic systems to create next‑generation dilution fridges for quantum data centers and 3‑D multi‑mode qubit architectures. By translating decades of superconducting accelerator infrastructure into quantum hardware, Fermilab positions itself to accelerate breakthroughs in health, energy and sustainability, where quantum computing promises to solve problems beyond classical capabilities.