Cyclotron–phonon resonance line-width in monolayer silicene.

We theoretically observe the cyclotron–phonon resonance (CPR) in monolayer silicene by considering the magneto-optical absorption power (AP) of the system. The AP is calculated utilising the projection operator technique when a static magnetic field is subjected perpendicularly to the plane of the material and the electron–optical phonon scattering is involved. The absorption spectra show the resonance behaviour where the photon energies at resonant peaks satisfy the cyclotron–phonon (CPR) conditions in which the CPR energy depends linearly on the square root of the magnetic field strength. This dependence is similar to that in graphene and different from that in monolayer MoS 2 and conventional low-dimensional semiconductors. The dependence of the full-width at half maximum (FWHM) on the magnetic field strength has the laws similar to those obtained for graphene and monolayer MoS 2. However, the FWHM value in silicene is two times smaller than it is in graphene and has the same order as it does in monolayer MoS 2. At relatively high temperature (T > 300 K), the FWHM for phonon emission differs very little from that for phonon absorption and becomes identical in two cases when T > 350 K. • The cyclotron–phonon resonance is observed in the absorption spectra. • The CPR energy is proportional to the square root of magnetic field strength. • The FWHM is proportional to the square root of magnetic field strength. • The FWHM increases slightly with increasing temperature. • At high temperatures the roles of phonon emission and phonon absorption are identical. [ABSTRACT FROM AUTHOR]