SERF Atomic Magnetometer (2D)

This 2D companion to the 3D SERF atomic magnetometer simulator strips the vapor cell down to a pannable, zoomable top-down view driven by the exact same Bloch-equation model. A vapor of alkali atoms is optically pumped into a polarized spin state, an adjustable field B_z makes that polarization precess, and a probe beam reads out the transverse component as the sensor's output signal. Raise the vapor density and spin-exchange collisions between atoms — which would normally dephase the ensemble — instead suppress each other through motional narrowing whenever the precession is slow compared to the collision rate, carving out the narrow, steep dispersive response near zero field that gives SERF sensors femtotesla-class sensitivity. Every control drives the same live Bloch-equation solution feeding both the 2D spin ensemble and the response-curve readout; drag the cell to pan and scroll to zoom in on individual atom spins.