title: Four-channel optically pumped atomic magnetometer for magnetoencephalography.
abstract: We have developed a four-channel optically pumped atomic magnetometer for magnetoencephalography (MEG) that incorporates a passive diffractive optical element (DOE). The DOE allows us to achieve a long, 18-mm gradiometer baseline in a compact footprint on the head. Using gradiometry, the sensitivities of the channels are < 5 fT/Hz1/2, and the 3-dB bandwidths are approximately 90 Hz, which are both sufficient to perform MEG. Additionally, the channels are highly uniform, which offers the possibility of employing standard MEG post-processing techniques. This module will serve as a building block of an array for magnetic source localization.
authors.forename: Anthony P
authors.initials: AP
authors.lastname: Colombo
authors.forename: Tony R
authors.initials: TR
authors.lastname: Carter
authors.forename: Amir
authors.initials: A
authors.lastname: Borna
authors.forename: Yuan-Yu
authors.initials: YY
authors.lastname: Jau
authors.forename: Cort N
authors.initials: CN
authors.lastname: Johnson
authors.forename: Amber L
authors.initials: AL
authors.lastname: Dagel
authors.forename: Peter D D
authors.initials: PD
authors.lastname: Schwindt
mesh_terms: D001921:Brain / Q000000981:diagnostic imaging*; D008280:Magnetics; D015225:Magnetoencephalography / Q000295:instrumentation*; D055096:Optical Devices