Event Abstract Back to Event Simultaneous MCG measurements with microfabricated atomic magnetometer and SQUID Svenja Knappe1*, Tilmann Sander2, Frank Wiekhorst2, John Kitching1 and Lutz Trahms2 1 NIST, United States 2 Physikalisch-Technische Bundesanstalt, Germany The magnetocardiogram (MCG) of the human heart was recorded simultaneously with a single channel microfabricated “chip-scale” atomic magnetometer (CSAM) and a low-temperature SQUID sensor array inside a magnetically shielded room. The atomic sensor had a sensitive volume of (2 mm)3 and was housed in a 1 cm3 enclosure that allowed a standoff distance of 3 mm. The sensor head was coupled to the laser control unit with optical fibers of length 5 m. Its fabrication by use of techniques common to micro-electro-mechanical systems (MEMS) allows for low operational complexity and potentially inexpensive mass fabrication. This sensor had a sensitivity below 500 fT/Hz1/2 in a range between 10 Hz and 500 Hz and had a bandwidth of roughly 1 kHz. Similar microfabricated magnetometers have demonstrated sensitivities of 65 fT/Hz1/2 [1] and even below 10 fT/Hz1/2 with more sophisticated optical setups [2]. Both for CSAM and SQUID, the normal component of the MCG was measured at different positions over the chest. Unaveraged data of the CSAM show the main features of the QRS complex and a subsequent averaging over several beats makes all QRS features visible. The higher noise in the CSAM compared to the SQUID is somewhat compensated by the close proximity of the CSAM to the heart. Future improvements of the CSAMs include multi-channel systems with variable sensor layouts and devices with higher sensitivity. The overall aim is to maintain the small size, wafer-level fabrication possibility, and simple coolant-free operation of CSAM sensors. We intended to demonstrate here the versatility and robustness of this type of optical magnetometers, which makes them practically very useful even if their sensitivity still needs to be improved.