  The dressed states arising from the interaction between electrons and holes,
and off-resonant electromagnetic radiation have been investigated for recently
fabricated gapped and anisotropic black phosphorus. Our calculations were
carried out for the low-energy electronic subbands near the $\Gamma$ point.
States for both linear and circular polarizations of the incoming radiation
have been computed. However, our principal emphasis is on linearly polarized
light with arbitrary polarization since this case has not been given much
attention for dressing fields imposed on anisotropic structures. We have
considered various cases for one- and few-layer phosphorus, including massless
Dirac fermions with tunable in-plane anisotropy. Initial Hamiltonian parameters
are renormalized in a largely different way compared to those for previously
reported for gapped Dirac structures and, most importantly, existing anisotropy
which could be modified in every direction.
