Skip to content
Volume 25, Issue 2
  • ISSN: 0032-1400


The wide range of use of the platinum resistance thermometer, roughly 10 to 1000K, is by no means enough to satisfy all demands for temperature standards. Ten years ago thermometers modelled on the capsule-type platinum thermometer but using an alloy of rhodium with 0.5 per cent iron were developed at the National Physical Laboratory specifically to provide standards for lower temperatures, and these are now widely used down to 0.5 K. In a recent joint experiment between the U.S. National Bureau of Standards and N.P.L., rhodium-iron has been used down to 0.01 K by coupling a small sample of the alloy to a resistive Such a device is capable of measuring accurately voltages of less than one nanovolt, and also of measuring the noise voltage in the resistor. Since the latter is dependent on the absolute temperature in a way that could be calculated, the device was able to provide its own calibration.


Article metrics loading...

Loading full text...

Full text loading...



  1. Coles B. R. 1964, Phys. Lett., 8, (4), 243 [Google Scholar]
  2. In the U.K. from the Oxford Instrument Company. From the physicists’ point of view cooling from 0.5 K to 0.005 K is as significant as cooling from 50 K to 0.5 K. Dilution refrigerators themselves are commonly used as a mere springboard for further coolings; see D. S. Betts, “Refrigeration and Thermometry below One Kelvin”, Sussex University Press and Chatto and Windus Ltd., London 1976. While concentrating on techniques, this book gives some inkling of the peculiar fascination of low temperature physics.
  3. Petley B. W. 1980, Contemp. Phys., 21, (6), 607 [Google Scholar]
  4. Soulen R. J., and Mashak H. 1980, Cryogenics, 20, 7, 408 [Google Scholar]
  5. Soulen R. J., Rusby R. L., and Van Vechten D. 1980, J. Low Temp. Phys., 40, (5/6), 553 [Google Scholar]

Data & Media loading...

  • Article Type: Research Article
This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error