Local magnetometry at high fields and low temperatures using InAs Hall sensors

We characterize the temperature (0.3 less than or equal to T less than or equal to 300 K), magnetic field (0 less than or equal to H less than or equal to 80 kOe), and thickness (0.1, 0.5, and 2.5 mu m) dependence of the Hall response of high purity InAs epilayers grown using metalorganic chemical vapor deposition. The high sensitivity, linearity, and temperature independence of the response make them attractive for local Hall probe magnetometry, and uniquely qualified for high field applications below liquid helium temperatures. As a stringent test of performance, we use a six element micron-sized array to monitor the internal field gradient during vortex avalanches at milliKelvin temperatures in a single crystal of YBa2Cu3O7-delta. (C) 1997 American Institute of Physics.