Rasser, RonjaRonjaRasserKoss, PeterPeterKossKnappe, SvenjaSvenjaKnappeBuse, KarstenKarstenBuse2025-08-182025-08-182025https://publica.fraunhofer.de/handle/publica/49062510.1140/epjqt/s40507-025-00400-yWe present a design for a multi-channel optically pumped zero-field magnetometer utilizing a 200-μm-thick Rubidium vapor cell. The vapor cell and its housing are designed to reduce the minimal distance between a magnetic sample and the sensing volume to about 1 mm, to optimize the effective spatial resolution. The thin vapor cell, filled with 2 atm of nitrogen as a buffer gas reduces the volume across which the magnetic field is averaged. The vapor cell is fully illuminated by a single laser beam, and the transmitted light is imaged onto a 4 x 4 photodiode array, allowing for simultaneous measurement of a magnetic field distribution with up to 16 channels. The performance of the magnetometer is studied for all channels. It is shown that the sensor can operate in the spin-exchange relaxation-free regime with a projected photon-shot noise limited noise floor of about 1 pT/Hz1/2 for a sensitive voxel size of approximately 600 μm x 600 μm x 200 μm.enSpin-exchange relaxation freeOptically pumped magnetometerImaging magnetic fieldsMulti-pixel optically pumped magnetometerImaging optically pumped magnetometerMagnetic field measurementjournal article