vdW Heterobilayers Research Articles

Electrical engineering of topological magnetism in two-dimensional heterobilayers

The emergence of topological magnetism in two-dimensional (2D) van der Waals (vdW) magnetic materials and their heterostructures is an essential ingredient for next-generation information technology devices. Here, we demonstrate the all-electric switching of the topological nature of individual magnetic objects emerging in 2D vdW heterobilayers. We show from the first principles that an external electric field modifies the vdW gap between CrTe2 and (Rh, Ti)Te2 layers and alters the underlying magnetic interactions. This enables switching between ferromagnetic skyrmions and meron pairs in the CrTe2/RhTe2 heterobilayer while it enhances the stability of frustrated antiferromagnetic merons in the CrTe2/TiTe2 heterobilayer. We envision that the electrical engineering of distinct topological magnetic solitons in a single device could pave the way for novel energy-efficient mechanisms to store and transmit information with applications in spintronics.

A study of 2D GeI2/InTe van der Waals hetero bilayer as a photocatalyst material

The computational study of the van der Waals hetero (vdW) bilayer GeI2/InTe has been carried out in present study. The isolated monolayer GeI2 and InTe have been studied first and the results were compared to the previous studies. The possible stackings are considered after the vdW interaction correction is applied in the structure relaxation. The vdW hetero bilayer stability has been checked from the phonon dispersion and ab initio Molecular Dynamics calculations. The charge transfer from InTe to GeI2 monolayer. Type-II indirect band gap (1.98, 2.01 eV) is verified by the projected band structure and band alignment calculations. The vdW hetero bilayer is a superior photocatalyst for the pH value up to pH = 0 to 11. The optical properties are calculated from the complex dielectric constant. The absorption coefficient shows the enhance absorption of light in the visible and ultraviolet regions. The vdW hetero bilayer has shown low reflectivity (37%) and a high refractive index (2.80) in the visible region. The enhanced optical properties have shown its possible applications in optoelectronic devices.

Coherent Phonons in van der Waals MoSe2/WSe2 Heterobilayers.

The increasing role of two-dimensional (2D) devices requires the development of new techniques for ultrafast control of physical properties in 2D van der Waals (vdW) nanolayers. A special feature of heterobilayers assembled from vdW monolayers is femtosecond separation of photoexcited electrons and holes between the neighboring layers, resulting in the formation of Coulomb force. Using laser pulses, we generate a 0.8 THz coherent breathing mode in MoSe2/WSe2 heterobilayers, which modulates the thickness of the heterobilayer and should modulate the photogenerated electric field in the vdW gap. While the phonon frequency and decay time are independent of the stacking angle between the MoSe2 and WSe2 monolayers, the amplitude decreases at intermediate angles, which is explained by a decrease in the photogenerated electric field between the layers. The modulation of the vdW gap by coherent phonons enables a new technology for the generation of THz radiation in 2D nanodevices with vdW heterobilayers.

Comprehensive study on electronic structures of SiGe/Ga$$_{2}$$SeTe vdW heterobilayer

Comprehensive study on electronic structures of SiGe/Ga$$_{2}$$SeTe vdW heterobilayer

Two-dimensional SiC/AlN based type-II van der Waals heterobilayer as a promising photocatalyst for overall water disassociation

Two-dimensional (2D) van der Waals (vdW) heterostructures made by vertical assembling of two different layers have drawn immense attention in the photocatalytic water disassociation process. Herein, we suggest a novel 2D/2D vdW heterobilayer consisting of silicon carbide (SiC) and aluminum nitride (AlN) as an exciting photocatalyst for solar-to-hydrogen conversion reactions using first-principles calculations. Notably, the heterostructure presents an inherent type-II band orientation wherein the photogenic holes and electrons are spatially separated in the SiC layer and the AlN layer, respectively. Our results indicate that the SiC/AlN heterostructure occupies a suitable band-gap of 2.97 eV which straddles the kinetic overpotentials of the hydrogen production reaction and oxygen production reaction. Importantly, the built-in electric field at the interface created by substantial charge transfer prohibits carrier recombination and further improves the photocatalytic performance. The heterostructure has an ample absorption profile ranging from the ultraviolet to the near-infrared regime, while the intensity of the absorption reaches up to 2.16 × 105 cm−1. In addition, external strain modulates the optical absorption of the heterostructure effectively. This work provides an intriguing insight into the important features of the SiC/AlN heterostructure and renders useful information on the experimental design of a novel vdW heterostructure for solar energy-driven water disassociation with superior efficiency.

Superior tunable photocatalytic properties for water splitting in two dimensional GeC/SiC van der Waals heterobilayers

The photocatalytic characteristics of two-dimensional (2D) GeC-based van der Waals heterobilayers (vdW-HBL) are systematically investigated to determine the amount of hydrogen (H2) fuel generated by water splitting. We propose several vdW-HBL structures consisting of 2D-GeC and 2D-SiC with exceptional and tunable optoelectronic properties. The structures exhibit a negative interlayer binding energy and non-negative phonon frequencies, showing that the structures are dynamically stable. The electronic properties of the HBLs depend on the stacking configuration, where the HBLs exhibit direct bandgap values of 1.978 eV, 2.278 eV, and 2.686 eV. The measured absorption coefficients for the HBLs are over ~ 105 cm−1, surpassing the prevalent conversion efficiency of optoelectronic materials. In the absence of external strain, the absorption coefficient for the HBLs reaches around 1 × 106 cm−1. With applied strain, absorption peaks are increased to ~ 3.5 times greater in value than the unstrained HBLs. Furthermore, the HBLs exhibit dynamically controllable bandgaps via the application of biaxial strain. A decrease in the bandgap occurs for both the HBLs when applied biaxial strain changes from the compressive to tensile strain. For + 4% tensile strain, the structure I become unsuitable for photocatalytic water splitting. However, in the biaxial strain range of − 6% to + 6%, both structure II and structure III have a sufficiently higher kinetic potential for demonstrating photocatalytic water-splitting activity in the region of UV to the visible in the light spectrum. These promising properties obtained for the GeC/SiC vdW heterobilayers suggest an application of the structures could boost H2 fuel production via water splitting.

Theoretical design of AlS-BS vdW heterobilayer for a promoted light energy utilization

Theoretical design of AlS-BS vdW heterobilayer for a promoted light energy utilization

Quantum Confinement Effects on Excitonic Properties in the 2D vdW quantum system: The ZnO/WSe2 Case

Quantum confinement effects play important roles in determining the electronic structures and optical properties of 2D quantum systems. Herein, the 2D ZnO/WSe2 van der Waals (vdW) system to study the influence of quantum confinement on excitonic optical properties, considering vdW heterobilayers (HBs), sandwiched trilayers (STs), and superlattice (SL), is taken. First‐principles calculations show that the quasiparticle (QP) bandgap, exciton binding energy, and band alignment depend obviously on quantum confinement. The QP bandgap and exciton binding energy decrease from 2.61 and 0.98 eV (HB) to 2.30 and 0.61 eV (ST), then to 2.02 and 0.28 eV (SL). Moreover, the conduction band offsets can be tuned from 0.87 eV (HB) to 0.79 eV (ST), then to 2.27 eV (SL). In addition, in ZnO/WSe2 vdW HB, increasing interlayer distance from 2.09 to 4.29 Å can induce exciton binding energy increase from 0.77 to 1.02 eV and QP bandgap increase from 2.49 to 2.62 eV. These results may be useful to tune excitonic properties and design optoelectronic devices by forming 2D vdW quantum systems.

Interlayer coupling effect in van der Waals heterostructures of transition metal dichalcogenides

Van der Waals (vdW) heterobilayers formed by two-dimensional (2D) transition metal dichalcogenides (TMDCs) created a promising platform for various electronic and optical properties, ab initio band results indicate that the band offset of type-II band alignment in TMDCs vdW heterobilayer could be tuned by introducing Janus WSSe monolayer, instead of an external electric field. On the basis of symmetry analysis, the allowed interlayer hopping channels of TMDCs vdW heterobilayer were determined, and a four-level k·p model was developed to obtain the interlayer hopping. Results indicate that the interlayer coupling strength could be tuned by interlayer electric polarization featured by various band offsets. Moreover, the difference in the formation mechanism of interlayer valley excitons in different TMDCs vdW heterobilayers with various interlayer hopping strength was also clarified.

Tunable Photocatalytic Properties of Planar GaN/GeC Hetero-Bilayer: Production of H₂ Fuel

Novel GaN-based van der Walls (vdW) hetero-bilayer (HBL) is systemically studied through the first-principles density functional theory (DFT) framework to explore its optoelectronic property facilitated photocatalytic activity for hydrogen (H2) fuel production. The vdW concept of planar GaN with GeC monolayer, together making stacked hetero-bilayer, shows unique and tunable optoelectronic properties that fulfill all the photocatalysis attributes. The confirmation of chemical and dynamical stabilities is made with negative interlayer binding energy and non-negative frequency in phonon spectra, respectively. Among the dynamically stable hetero-bilayers, binding energy in HBL 2 (AB1) is the lowest and interlayer distance ~2.954Å is the smallest. The HBLs are sensitive to the stacking arrangements, where HBL 2 demonstrates type-I direct bandgap and HBL 6 (AB6) is Type-II direct bandgap. The intrinsic HBLs show superior carrier mobility as their effective masses are lower from their constituent monolayers. Also, the intrinsic absorption coefficient of the HBLs increase as high as ~10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sup> cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> , 10 times greater than conventional perovskite materials, which show outperforming optoelectronic conversion efficiency. Additionally, the HBLs are highly tunable in both bandgap and type due to biaxial strains and cross-plane electric fields. With biaxial strains, from compressive to tensile, both HBLs show monotonous bandgap lowering with a dominant direct-indirect bandgap splitting in HBL 2. Interestingly, for all the biaxial strains within the -6% to +6% range, both HBLs have sufficient kinetic overpotential for photocatalytic water splitting and an increase in visible peak by 3.5 (2) times in the HBL 6 (HBL 2). Electric fields also increase the photocatalytic water splitting performance with a net bandgap lowering and increasing the visible absorption peak by ~1.5 times compared with intrinsic HBLs. These promising properties that we have found in the planar GaN/GeC vdW hetero-bilayer are highly suggestive for the impending use of this material in photocatalytic water splitting technology to produce H2 fuel.

Interfacing Boron Monophosphide with Molybdenum Disulfide for an Ultrahigh Performance in Thermoelectrics, Two-Dimensional Excitonic Solar Cells, and Nanopiezotronics.

A stable ultrathin 2D van der Waals (vdW) heterobilayer, based on the recently synthesized boron monophosphide (BP) and the widely studied molybdenum disulfide (MoS2), has been systematically explored for the conversion of waste heat, solar energy, and nanomechanical energy into electricity. It shows a gigantic figure of merit (ZT) > 12 (4) for p (n)-type doping at 800 K, which is the highest ever reported till date. At room temperature (300 K), ZT reaches 1.1 (0.3) for p (n)-type doping, which is comparable to experimentally measured ZT = 1.1 on the PbTe-PbSnS2 nanocomposite at 300 K, while it outweighs the Cu2Se-CuInSe2 nanocomposite (ZT = 2.6 at 850 K) and the theoretically calculated ZT = 7 at 600 K on silver halides. Lattice thermal conductivity (κl ≈ 49 W m-1 K-1) calculated at room temperature is lesser than those of black phosphorene (78 W m-1 K-1) and arsenene (61 W m-1 K-1). The nearly matched lattice constants in the commensurate lattices of the constituent monolayers help to preserve the direct band gap at the K point in the type II vdW heterobilayer of MoS2/BP, where BP and MoS2 serve as donor and acceptor materials, respectively. An ultrahigh carrier mobility of ∼20 × 103 cm2 V-1 s-1 is found, which exceeds those of previously reported transition metal dichalcogenide-based vdW heterostructures. The exciton binding energy (0.5 eV) is close to those of MoS2 (0.54 eV) and C3N4 (0.33 eV) single layers. The calculated power conversion efficiency (PCE) in the monolayer MoS2/BP heterobilayer exceeds 20%. It surpasses the efficiency in MoS2/p-Si heterojunction solar cells (5.23%) and competes with the theoretically calculated ones, as listed in the manuscript. Furthermore, a high optical absorbance (∼105 cm-1) of visible light and a small conduction band offset (0.13 eV) make MoS2/BP very promising in 2D excitonic solar cells. The out-of-plane piezoelectric strain coefficient, d33 ≈ 3.16 pm/V, is found to be enhanced 4-fold (∼14.3 pm/V) upon applying 7% vertical compressive strain on the heterobilayer, which corresponds to ∼1 kbar of hydrostatic pressure. Such a high out-of-plane piezoelectric coefficient, which can tune top-gating effects in ultrathin 2D nanopiezotronics, is a relatively new finding. As BP has been synthesized recently, experimental realization of the multifunctional, versatile MoS2/BP heterostructure would be highly feasible.

Interface-controlled band alignment transition and optical properties of Janus MoSSe/GaN vdW heterobilayers

Since the Janus MoSSe monolayer was fabricated in 2017, it has attracted increasing attention because the out-of-plane mirror symmetry is broken. Here, based on first-principles calculations, we construct theoretically 2D Janus MoSSe/GaN van der Waals (vdW) heterobilayers, and demonstrate that it has direct band structure and a broad optical absorption spectrum from visible to the UV region. Interestingly, the S- and Se-interface can induce straddling type-I and staggered type-II band alignments, and the gap values are modified. Moreover, the interlayer coupling and electronic field effects on electronic structures depend on the interface characteristics in Janus MoSSe/GaN heterobilayers. The studies provide the idea to modify the electronic characteristics using interface characteristics in the 2D materials-based vdW heterostructures.

Structural, electronic, and electromechanical properties of MoSSe/blue phosphorene heterobilayer

Two-dimensional (2D) materials attract considerable interest due to their outstanding electronic and mechanical properties. Although extensive efforts have been made on seeking of new kinds of 2D materials, individual ones can hardly offer all required properties for practical applications in nanoelectronics and optoelectronics. To integrate the advantages of each individual component, in this work, we predict the structural and electromechanical properties of 2D van der Waals (vdW) heterobilayers constructed with single-layer Janus transition metal dichalcogenides and blue phosphorus (e.g., SMoSe/BlueP and SeMoS/BlueP) by means of density-functional theory (DFT) based calculations. The vdW interactions were carefully taken into account by employing the DFT-DF correction functional. It is found that the proposed vdW heterobilayers are dynamically stable with enhanced elastic moduli. The SeMoS/BlueP heterobilayer is shown as a type-I semiconductor with an indirect bandgap of 1.55 eV, and SMoSe/BlueP is also a type-I semiconductor with a slightly larger indirect bandgap of 1.76 eV. In addition, the piezoelectronic response of the heterobilayers was also carefully explored. In particular, the out-of-plane piezoelectric response of SeMoS/BlueP that is characterized by the piezoelectric coefficient e311(d311) gets enhanced compared to the Janus MoSSe monolayer. Our findings demonstrate a great potential for their applications in energy harvesting and sensors at the nanoscale.

Theoretical design of a novel 2D tetragonal ZnS/SnO hetero-bilayer as a promising photocatalyst for solar water splitting

Van der Waals (vdW) hetero-bilayers are emerging as unique structures to enhance the performance of two-dimensional (2D) layered nanomaterials for next-generation electronic and optoelectronic devices. In this work, we employ first-principles calculations to study the novel tetragonal ZnS/SnO hetero-bilayer (BL). The state-of-the-art computations based upon quasiparticle GW and Bethe−Salpeter equation (BSE) are utilized to study the electronic and optical properties of this novel vdW hetero-bilayer. We reveal that ZnS/SnO BL is a polarized semiconductor with a clear built-in electric field, and possesses a special band characteristic favorable for reducing the carrier recombination. It is also demonstrated that strain and external electric field are among the effective methods to modulate the electronic and optical properties of ZnS/SnO BL. Our work suggests that ZnS/SnO BL has an excellent optical absorption in the solar spectrum, rendering the material a viable candidate for optoelectronic applications, in particular for solar water splitting.

ZrS3/MS2 and ZrS3/MXY (M[dbnd]Mo, W; X, Y[dbnd]S, Se, Te; X ≠ Y) type-II van der Waals hetero-bilayers: Prospective candidates in 2D excitonic solar cells

Excellent photovoltaic abilities in a 2D excitonic solar cell based on staggered type-II van der Waals (vdW) hetero-bilayers comprising of semiconducting ZrS3 monolayer and monolayers of MS2 & MXY (MMo, W; X, YS, Se, Te; X ≠ Y) are reported herewith, using DFT-D2 and HSE06 functional. Studies on vdW hetero-bilayers of MX3/MX2 and MX3/M'Y2 have so far been conveniently avoided on account of their large lattice mismatch. The present work is the first attempt to address such hetero-bilayers constituted by monolayers of transition metal dichalcogenides and trichalcogenides. The nature of the band edges in ZrS3 and MS2 monolayers induces high electron and hole mobility in these individual monolayers, respectively, which has been combined synergistically in the hetero-bilayers consisting of them. The Power Conversion Efficiency (PCE) in ZrS3/MoS2, ZrS3/WS2, ZrS3/MoSeTe, ZrS3/WSTe, and ZrS3/WSeTe hetero-bilayers, calculated within the Anderson-limit, are found to reach as high as ~12%, 8%, 16%, 14%, and 14% respectively. The PCE of the hetero-bilayers reported herewith are much higher than the efficiency in MoS2/p-Si heterojunction solar cells (5.23%) and comparable to that of the theoretically proposed PCBM fullerene/BCN system (10–20%) and g-SiC2-based systems (12–20%) and the recently predicted TiNF/TiNBr (18%), TiNCl/TiNBr (19%), TiNF/TiNCl (22%) bilayer solar cell systems.

Electronic and optical properties of the ZrS2/HfSe2 van der Waals heterobilayer with native type-II band alignment

Two-dimensional (2D) semiconductors have been attracting considerable interests for the potential applications in nano-optoelectronic devices. Here, we study the electronic and optical properties of the ZrS2/HfSe2 van der Waals (vdW) heterobilayer, which presents an intrinsic type-II band alignment. The conduction band minimum (CBM) and the valence band maximum (VBM) are separately dominated by the ZrS2 and HfSe2 layers, respectively. More importantly, the superior optical absorption of the heterostructure can be reached to the 106 amounts in ultraviolet region. Our results suggest that the 2D ZrS2/HfSe2 vdW heterobilayer would be likely utilized in the optoelectronic devices.

Photo-absorption properties of van der Waals heterostructure of monolayer InSe with silicene, germanene and antimonene

In this work, we study van der Waals (vdW) heterostructures consisting of the emerging photonic material, 2-dimensional (2D) InSe, with the lattice-matched 2D materials silicene, germanene and antimonene, using ab-initio simulations. We employ density functional theory (DFT) to calculate the structural and electronic properties of the vdW hetero-bilayers. The optical spectra of the systems are evaluated by solving the Bethe-Salpeter equation (BSE) on top of the GW quasiparticle bands. A strong response in the IR-visible region of the optical spectra is seen in case of InSe-Si and InSe-Ge vdW lattice whereas the InSe-Sb structure shows better performance in the visible-UV region, with better prospect of excitonic charge separation. A good absorbance in the IR-visible and the visible-UV region, can be achieved with these structures with computed theoretical photocurrent densities significantly larger than conventional photovoltaic materials. While individually the vdW structures can be useful in photonic applications, the complimentary nature of absorption with InSe-Sb and InSe-Si/Ge structures can also be utilized in multi-junction heterostructure solar cells.

Superhigh out-of-plane piezoelectricity, low thermal conductivity and photocatalytic abilities in ultrathin 2D van der Waals heterostructures of boron monophosphide and gallium nitride.

A stable 2D van der Waals (vdW) heterobilayer, constituted by boron monophosphide (BP) and Gallium Nitride (GaN) monolayers, has been explored for different kinds of energy conversion and nanoelectronics. The nearly matched lattice constants of GaN and BP are commensurate with each other in their lattice structures. The out-of-plane inversion asymmetry coupled with the large difference in atomic charges between the GaN and BP monolayers induces in the heterobilayer a giant out-of-plane piezoelectric coefficient (|d33|max ≈ 40 pm V-1), which is the highest ever reported in 2D materials of a finite thickness. It is much higher than the out-of-plane piezoelectric coefficient reported earlier in multilayered Janus transition metal dichalcogenide MXY (M = Mo, W; X, Y = S, Se, Te) (|d33|max = 10.57 pm V-1). Such a high out-of-plane piezoelectricity found in a BP/GaN heterobilayer can bring about gigantic strain-tunable top gating effects in nanopiezotronic devices based on the same. Moreover, electron mobility (∼104 cm2 V-1 s-1) is much higher than that of transition metal dichalcogenides and conventional semiconductors. The origin of low lattice thermal conductivity (κL ∼ 25.25 W m-1 K-1) in BP/GaN at room temperature, which is lower than that of black phosphorene (78 W m-1 K-1), buckled arsenene (61 W m-1 K-1), BCN (90 W m-1 K-1), MoS2 (34.5 W m-1 K-1) and WS2 (32 W m-1 K-1) monolayers, has been systematically investigated via phonon dispersion, lattice thermal conductivity, phonon lifetime and mode Grüneisen parameters. The valence band maximum (VBM) and conduction band minimum (CBM) arising from GaN and BP monolayers respectively result in a type II vdW heterobilayer, which is found to be thermodynamically favorable for photocatalytic water splitting in both acidic and neutral media. The exciton binding energies are comparable to those of MoS2 and C3N4 single layers, while the absorbance reaches as high as ∼105 cm-1 in the visible wavelength region. The emergence of high piezoelectricity, high carrier mobility, low lattice thermal conductivity and photocatalytic water splitting abilities in the proposed vdW heterobilayer signifies enormous potential for its versatile applications in nanoscale energy harvesting, e.g., nano-sensors in medical devices, future nanopiezotronics, 2D thermoelectrics and solar energy conversion.

Trends on band alignments: Validity of Anderson's rule inSnS2- andSnSe2-based van der Waals heterostructures

Van der Waals (vdW) heterostructures are promising candidates for building blocks in novel electronic and optoelectronic devices with tailored properties, since their electronic action is dominated by the band alignments upon their contact. In this work, we analyze 10 vdW heterobilayers based on tin dichalcogenides by first-principles calculations. Structural studies show that all systems are stable, and that commensurability leads to smaller interlayer distances. Using hybrid functional calculations, we derive electronic properties and band alignments for all the heterosystems and isolated two-dimensional (2D) crystals. Natural band offsets are derived from calculated electron affinities and ionization energies of 11 freestanding 2D crystals. They are compared with band alignments in true heterojunctions, using a quantum mechanical criterion, and available experimental data. For the ${\mathrm{hBN}/\mathrm{SnSe}}_{2}$ system, we show that hBN suffers an increase in band gap, while leaving almost unchanged the electronic properties of ${\mathrm{SnSe}}_{2}$. Similarly, ${\mathrm{MX}}_{2}$ (M = Mo, W; X = S, Se) over ${\mathrm{SnX}}_{2}$ preserve the natural discontinuities from each side of the heterobilayer. Significant charge transfer occurs in junctions with graphene, which becomes p-doped and forms an Ohmic contact with ${\mathrm{SnX}}_{2}$. Zirconium and hafnium dichalcogenides display stronger interlayer interactions, leading to larger shifts in band alignments with tin dichalcogenides. Significant orbital overlap is found, which creates zero conduction band offset systems. The validity of the Anderson electron affinity rule is discussed. Failures of this model are traced back to interlayer interaction, band hybridization, and quantum dipoles. The systematic work sheds light on interfacial engineering for future vdW electronic and optoelectronic devices.

Topological mosaics in moiré superlattices of van der Waals heterobilayers

Van der Waals (vdW) heterostructures formed by 2D atomic crystals provide a powerful approach towards designer condensed matter systems. Incommensurate heterobilayers with small twisting and/or lattice mismatch lead to the interesting concept of Moir\'e superlattice, where the atomic registry is locally indistinguishable from commensurate bilayers but has local-to-local variation over long range. Here we show that such Moir\'e superlattice can lead to periodic modulation of local topological order in vdW heterobilayers formed by two massive Dirac materials. By tuning the vdW heterojunction from normal to the inverted type-II regime via an interlayer bias, the commensurate heterobilayer can become a topological insulator (TI), depending on the interlayer hybridization controlled by the atomic registry between the vdW layers. This results in mosaic pattern of TI regions and normal insulator (NI) regions in Moir\'e superlattices, where topologically protected helical modes exist at the TI/NI phase boundaries. By using symmetry based k.p and tight-binding models, we predict that this topological phenomenon can be present in inverted transition metal dichalcogenides heterobilayers. Our work points to a new means of realizing programmable and electrically switchable topological superstructures from 2D arrays of TI nano-dots to 1D arrays of TI nano-stripes.