Ultra-low field magnetic resonance imaging detection with gradient tensor compensation in urban unshielded environment
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All-optical magnetometry for NMR detection in a micro-Tesla field and unshielded environment.
An all-optical atomic magnetometer is used to detect a proton free-precession signal from a water sample polarized in a 0.7 T field and remotely analyzed in a 4 microT field. Nuclear spins are manipulated either by pi/2 pulses or by non-adiabatic rotation. The magnetometer operates at room temperature, in an unshielded environment and has a dual-channel sensor for differential measurements.
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تاریخ انتشار 2013