Fig. 1: Simplified 1d encoding scheme in a transmission mode experiment.
From: Neutral beam microscopy with a reciprocal space approach using magnetic beam spin encoding
The beam particles (blue circles) move from left to right along the \(\hat{{{{\boldsymbol{z}}}}}\)-axis, and the arrows encapsulated within the circles represent the magnetic moment of the beam particles. The polarised beam has all its magnetic moments oriented along \(\hat{{{{\boldsymbol{x}}}}}\) initially. The beam interacts with a sample, which blocks some of the trajectories, resulting in \(P(x,y)\) being zero for specific \(x\), \(y\) positions. As the particles move within the encoding device, their magnetic moments precess in the \({xz}\) plane in a way that depends on the field strength and correspondingly on their x position. The precession stops when the particles leave the encoding device. A spin analyser transmits the particles to a detector in a way that depends on the orientation of their magnetic moment with respect to the analyser projection axis. Note that the missing trajectories which were blocked by the sample change the average magnetic moment orientation of the beam and correspondingly, the signal the detector will measure.
