mK

millikelvin

Temperatureexact by definition

A millikelvin is 10⁻³ K, an exact SI prefix. It is the everyday unit of dilution-refrigerator work: superconducting qubits run near 10 mK, and the base temperature of a commercial cryostat is quoted in millikelvin because quoting it in kelvin would hide the difference between a good machine and a great one.

1 mK -273.149 °C