Perpendicular electric field effects on the propagation of electromagnetic waves through the monolayer phosphorene

摘要

The electric field-induced optical activity of monolayer phosphorene within the framework of effective anisotropic tight-binding model and the linear response theory is studied. The optical conductivity tensor is derived using the Kubo formula and an incident circular electromagnetic wave is applied perpendicularly to the phosphorene's plane. By dividing the optical frequency into three regimes, beneath, near and above the band gap, the electric-field-dependent measurement of the stretching and rotation angle of the polarization ellipse is investigated in details. Beneath the band gap, both reflected and transmitted lights are almost polarized linearly independent of the gate voltage, however, the polarization can be tuned via the electric field for the frequencies near and above the band gap. Our results show that, at certain electric fields, rotation angle 180 degrees of the polarization ellipse belongs only to the frequencies above the band gap. Additionally, the absorption in phosphorene is possible up to a few percents, confirming the transparency of monolayer phosphorene. The findings here pave the way for setting up the real applications in optoelectronics.