Journal Of The Optical Society Of America B-Optical Physics, cilt.37, sa.7, ss.2128-2138, 2020 (SCI-Expanded)
We investigate linear and nonlinear spectral singularities in the transverse electric and transverse magnetic
modes of a slab laser consisting of an active planar slab sandwiched between a pair of Graphene
or Weyl semimetal thin sheets. The requirement of the presence of linear spectral singularities gives the
laser threshold condition while the existence of nonlinear spectral singularities due to an induced weak
Kerr nonlinearity allows for computing the laser output intensity in the vicinity of the threshold. The
presence of the Graphene and Weyl semimetal sheets introduces additional physical parameters that we
can use to tune the output intensity of the laser. We provide a comprehensive study of this phenomenon
and report peculiarities of lasing in the TM modes of the slab with Weyl semimetal coatings. In particular,
we reveal the existence of a critical angle such that no lasing seems possible for TM modes of the slab with
smaller emission angle. Our results suggest that for TM modes with emission angle slightly exceeding
the critical angle, the laser output intensity becomes highly sensitive to the physical parameters of the
coating.