Introduction to Johnson Noise Thermometry - Page 1

Hello and welcome to this presentation on the worlds first practical Johnson noise thermometer. Johnson noise has for many years been used by metrologists as a means of measuring temperature but so far these devices have been limited to expensive, room sized experiments whose purpose was to determine true thermodynamic in order to ensure that our practical temperature scales such as the Kelvin, Celsius or Fahrenheit scales closely match the thermodynamic definition of temperature. The great advantage of Johnson noise thermometers is that the signal they measure is fundamentally linked to the true thermodynamic temperature of the thermometer’s sensor and so are incapable of drift.