​Rhodium-iron sensors have been discontinued. Alternative sensors are Cernox for measuring temperatures from 100 mK to 420 K or Platinum for measuring temperatures from 14 K to 873 K.

Rhodium-Iron Features

  • ​Good long term stability: ±10 mK from 1.4 K to 325 K
  • RF-800 offers a wide temperature range from 0.65 K to 500 K
  • Linear response above 100 K
  • Excellent resistance to ionizing radiation
  • Small chip size available with extremely fast thermal response time

Rhodium-iron cryogenic temperature sensors offer a positive temperature coefficient, monotonic response over a wide temperature range, and high resistance to ionizing radiation.


The RF-800 rhodium-iron resistance sensor features monotonically decreasing resistivity from 500 K to 0.65 K, although sensitivity (dR/dT) falls off in the region of 30 K. From 100 K to 273 K the resistance changes linearly with temperature to within 1 K. RF-800-4 sensors also exhibit monotonic response at higher temperatures, hence their adaptability for use over the broad range from 1.4 K to 500 K.

packaging optionsRF-800

Lead extensions