Tunable electronic and magneto-optical properties of monolayer arsenene: From $\mathrm{G}{\mathrm{W}}_0$ approximation to large-scale tight-binding propagation simulations

Monolayers of the group called VA elements have attracted great attention with the rising of black phosphorus. Here, we derive a simple tight-binding model for monolayer grey arsenic, referred to as arsenene (ML-As), based on the first-principles calculations within the partially self-consistent $\mathrm{G}{\mathrm{W}}_0$ approach. The resulting band structure derived from the six $p$-like orbitals coincides with the quasiparticle energy from $\mathrm{G}{\mathrm{W}}_0$ calculations with a high accuracy. In the presence of a perpendicular magnetic field, ML-As exhibits two sets of Landau levels linear with respect to the magnetic field and level index. Our numerical calculation of the optical conductivity reveals that the obtained optical gap is very close to the $\mathrm{G}{\mathrm{W}}_0$ value and can be effectively tuned by external magnetic field. Thus, our proposed TB model can be used for further large-scale simulations of the electronic, optical, and transport properties of ML-As.

Figure 1

Atomic structure of ML-As. (a) Top view of ML-As with the unit cell indicated by the black rhombus. The green balls are arsenic atoms. (b) Real-space distribution of the WFs at one sublattice, where three $p$-like orbitals are situated.

Figure 2

Hopping diagram in the TB model of ML-As. The orbitals are represented by the negative part of the $p$-like orbitals as indicated by the red ellipses.

Figure 3

Electronic properties of ML-As. (a) Band structure and DOS of ML-As. The red and black colors present the $\mathrm{G}{\mathrm{W}}_0$ and TB results, respectively. (b) Effective mass of carriers derived from the TB model in the unit of free electron mass $m_0$. The EMs of the first CB (electron) and first two VBs (hole) are presented in red and blue, respectively.

Figure 4

DOS of ML-As under perpendicular magnetic field. The DOS is extracted from the inset with less dense peaks. Red and blue represents the LLs of electrons and holes, respectively.

Figure 5

LL spectrum of ML-As in high magnetic field. The lowest fifty LLs calculated from the linear fitting of Eq. (10) are indicated by the red dashed lines. The green circles are LLs obtained from the tight-binding propagation method.

Figure 6

Magneto-optical properties of ML-As. The optical conductivity spectrum of ML-As is calculated with $\mathbf{B}=0\mathrm{T}$ (black), 12.5 T (red), 25 T (blue), and 50 T (green), respectively. The inset shows the optical conductivity in a much wider energy window. ${\sigma }_0=e^2/4\hslash$ is the universal optical conductivity. The first four peaks are present in orange for reference.