Reliefs of the Determinant in the Threshold Condition Analysis of a Micro/Nano Laser on a Single Graphene Strip in a Circular Quantum Wire

The reliefs of the determinant, i.e., the absolute values of the determinant as a function of frequency and threshold material gain, are analyzed. The considered geometry includes a symmetrically placed single graphene strip in a circular quantum wire. The directory names correspond to the geometric parameters (in micrometers), while the file name represents the chemical potential of the graphene strip (in electron volts). The frequency values are given in THz. The real part of the permittivity of the wire material is 2.25, corresponding to a refractive index of 1.5.