# Monitors
monitors: List of monitors in the simulation. Note: monitor names are used to access data after the simulation is run.
The scattering matrix and the port modes are always computed by an EME simulation and do not require a monitor; see EME Results. Monitors record additional data inside the simulation domain.
Options:
- EME Field Monitor: records the propagated electromagnetic field.
- EME Mode Solver Monitor: records the modes computed in the EME cells.
- EME Coefficient Monitor: records the forward and backward mode coefficients in each cell.
EME monitors record at the simulation frequencies defined in Wavelengths. Each monitor can select a subset of these values but cannot add new ones. Monitors can also limit the number of recorded modes and sweep indices to reduce the amount of stored data.