▎ 摘　　要

The realization of quantitative, noninvasive sensors for ambient magnetic imaging with high spatial and magnetic field resolution remains a major challenge. To address this, we have developed a relatively simple process to fabricate semi-encapsulated graphene/hBN Hall sensors assembled by dry transfer onto pre-patterned gold contacts. 1 mu m-sized Hall cross sensors at a drive current of 0.5 mu A exhibit excellent room temperature sensitivity, S-I similar to 700V/AT, and good minimum detectable fields, B-min=0.54G/Hz(0.5) at a measurement frequency of 1kHz, with considerable scope for further optimization of these parameters. We illustrate their application in an imaging study of labyrinth magnetic domains in a ferrimagnetic yttrium iron garnet film. (C) 2022 Author(s).