Novel wide spectrum light absorber heterostructures based on hBN/In(Ga)Te

Abstract

Two-dimensional group III monochalcogenides have recently attracted quite attention for their wide spectrum of optical and electric properties, being promising candidates for optoelectronic and novel electrical applications. However, in their pristine form they are extremely sensitive and vulnerable to oxygen in air and need good mechanical protection and passivization. In this work we modeled and studied two newly designed van der Waals (vdW) heterostructures based on layer of hexagonal boron nitride (hBN) and GaTe or InTe monolayer. Using density functional theory, we investigate electronic and optical properties of those structures. Their moderate band gap and excellent absorption coefficient makes them ideal candidate for broad spectrum absorbers, covering all from part of IR to far UV spectrum, with particularly good absorption of UV light. The hBN layer, which can be beneficial for protection of sensitive GaTe and InTe, does not only preserve their optical properties but also enhances it by changing the band gap width and enhancing absorption in low-energy part of spectrum. Calculated binding energies prove that all three stacking types are possible to obtain experimentally, with H-top as the preferable stacking position. Moreover, it is shown that type of stacking does not affect any relevant properties and bandstructure doesn’t reveal any significant change for each stacking type.

Strain-induced modulation of electronic and optical properties in hBN/InSe heterostructure

“…Similarly to hBN/InTe and hBN/GaTe HSs reported in our previous work [51,52], hBN/InSe HS is modeled as supercell composed of 1x1 unit cell of InSe, with √ 3 × √ 3 supercell of hBN rotated for 30 • on top of InSe. Drawing parallels with our previous studies, this approach ensures consistency in our methodology.…”

Tailoring Electronic and Optical Properties of hBN/InTe and hBN/GaTe Heterostructures Through Biaxial Strain Engineering

“…As discussed in our previous work 32 , hBN/In(Ga)Te HS is modelled as a supercell consisting of a single layer of In(Ga)Te(1x1) on top of the single layer hBN( √ 3 × √ 3) supercell, resulting in a hexagonal unit cell with a lattice constant of a = 4.336 Å for hBN/InTe and a = 4.309 Å for hBN/GaTe. The top view of the structures is presented in Figure 1.…”

“…In our investigation, we computed the band structures of both heterostructures (HSs) under various compressive and tensile strain conditions, building upon the foundation laid out in our previous study 32 . The band structures for HSs under -4%, 0% and 4% strain are visually represented in Figure 3.…”

“…Motivated by these results, in our previous work, we designed and investigated two novel heterostructures, hBN/InTe and hBN/GaTe, as detailed in 32 . These heterostructures displayed favourable electronic properties and an excellent broad absorption spectrum, enhanced and protected by the hBN layer, making them promising candidates for applications in photodetectors or field-effect transistors.…”

Tunable electronic properties and optoelectronic characteristics of MoGe2N4/SiC van der Waals heterostructure

“…Compared to the materials traditionally employed in optoelectronic devices, 2D materials exhibit superior transport properties and optical characteristics [52,53]. Consequently, we have individually fabricated optoelectronic devices using monolayers of SiC, MoGe 2 N 4 , and a MoGe 2 N 4 /SiC heterostructure (taking the AA stacking configuration as an example) to investigate their photodetection performance.…”