Properties of the commercially available magnetoresistive sensor KMZ10A in the temperature range between 50 and 290 K

We have performed experimental investigations in order to determine the sensitivity and the resistance of the KMZ10A magnetoresistive (MR) sensor in the temperature range between 50 and 290 K by using a cryocooler. The sensitivity increases for a decrease of temperature whereas the resistance decreases. At 50 K the MR sensor shows 1.33 times the sensitivity that it does at 290 K. The resistance at 50 K is 0.52 times the resistance at 290 K. Noise measurements performed in a cryoperm shielding at room temperature and at 77 K in liquid nitrogen have shown that the voltage fluctuation in the white noise range of the MR sensor is equal to that of an equivalent resistor leading to a resolution of 44 pT/root Hz at room temperature and 13 pT/root Hz at 77 K. (C) 1997 Elsevier Science Ltd. All rights reserved.