Intra- and inter-band magneto-optical absorption in monolayer WS2

In this paper, the optical absorption coefficients (OACs) and the refractive index changes (RICs) due to both intra- and inter-band transitions in monolayer WS2 are theoretically investigated in the presence of a magnetic field. The results showed that both OACs and RICs display the blue-shift behavior with the increase of the magnetic field. The Zeeman fields have no effect on the peak positions but reduce slightly peak intensities. Besides, the strong spin–orbit coupling in monolayer WS2 causes the significant difference of the peak due to spin up and down. The OACs and RICs due to intra-band transition display only one peak in the THz range, while the inter-band spectra show a series of peaks in the near-infrared to the visible optical range, making monolayer WS2 to be a promising candidate for novel optoelectronic applications. •Optical spectra display the blue-shift behavior when the magnetic field increase.•The Zeeman fields do not affect the peak positions but reduce slightly their intensities.•The strong SOC in monolayer WS2 causes the significant difference of the peak due to spin up and down.•Peaks due to intraband transitions are in the THz range.•The interband spectra show a series of peaks in the near-infrared to the visible optical range.