  The Roman Coronagraph is expected to perform its high-order wavefront sensing
and control (HOWFSC) with a ground-in-the-loop scheme due to the computational
complexity of the Electric-Field-Conjugation (EFC) algorithm. This scheme
provides the flexibility to alter the HOWFSC algorithm for given science
objectives. A new alternative implicit-EFC algorithm is of particular interest
as it requires no optical model to create a dark-hole, making the final
contrast independent of the model accuracy. The intended HOWFSC scheme involves
running EFC while observing a bright star such as $\zeta$ Puppis to create the
initial dark-hole, then slew to the science target while maintaining the
contrast with low-order WFSC over the given observation.
  Given a similar scheme, the efficacy of iEFC is simulated for two coronagraph
modes, namely the Hybrid Lyot Coronagraph (HLC) and the wide-field-of-view
Shaped-Pupil-Coronagraph (SPC-WFOV). End-to-end physical optics models for each
mode serve as the tool for the simulations. Initial monochromatic simulations
are presented and compared with monochromatic EFC results obtained with the
FALCO software. Various sets of calibration modes are tested to understand the
optimal modes to use when generating an iEFC response matrix. Further iEFC
simulations are performed using broadband images with the assumption that
$\zeta$ Puppis is the stellar object being observed. Shot noise, read noise,
and dark current are included in the broadband simulations to determine if iEFC
could be a suitable alternative to EFC for the Roman Coronagraph.
