Hall Sensors Calibration for Operation Above 2 T at 77 K

Abstract

This paper presents a calibration of seven low-cost CYSJ362A GaAs Hall sensors operating in liquid nitrogen at 77 K and magnetic flux densities above 2 T. A non-magnetic solenoid coil was used as a reference field source, and the sensor response was modeled using polynomial regression of the Hall voltage–flux density characteristic. Statistical model selection identified a fifth-order polynomial as an optimal compromise between accuracy and model complexity. Measurement uncertainty was quantified using analytical error propagation combined with Monte Carlo simulation, accounting for current measurement,  coil geometry,  and  sensor positioning. The dominant contribution to the uncertainty was the current  measurement (≈ 3%),  while  for  magnetic  flux  densities above 2 T, the combined standard uncertainty reached ≈ 10%. The results demonstrate good repeatability under pulsed excitation and confirm the suitability of low-cost GaAs Hall sensors for multi-point magnetic field measurements in high-temperature superconductor experiments.