Assessment of performance potential of MoS2-based topological insulator field-effect transistors

Liu, Leitao; Guo, Jing

doi:10.1063/1.4930930

Cited by 12 publications

(6 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…S, Se, Te etc.) atoms respectively, were first predicted to possess the topological properties by Qian et al 35 and later it was verified by several other investigations [36][37][38][39][40][41][42][43][44][45][46][47][48] . Based on first principles calculations and tight-binding Hamiltonian, they demonstrated 35 that among several polytypic structures, 1T' phase of a monolayer TMD features band inversion in its bulk energy spectrum.…”

Section: Investigation Of Quantum Spin Hall States In 1t' Phase Of Thmentioning

confidence: 85%

“…However, from an engineering viewpoint, it is highly desirable to devise a method to control the transport through edge states by external means which forms the notion of topological insulator field effect transistors (TIFET) 50 . The most straightforward solution would be rapidly introducing and removing the edge states through topological phase transition, which for 1T' TMDs has been demonstrated by applying vertical electric field 35,36 and strain 35 . Even, if the TRS is broken either by external perturbation (e.g.…”

Section: Investigation Of Quantum Spin Hall States In 1t' Phase Of Thmentioning

confidence: 99%

“…We start with a low-energy . ( ) H k p for monolayer 1T' MX 2 structures, as prescribed by Qian et al 35 and Liu et al 36 H k p define the inter-band interactions between them. Numeric values of δ p and δ d were directly obtained from the DFT data while the effective masses and velocities were obtained by calibrating the above Hamiltonian with DFT results.…”

Section: Development Of Kpmentioning

confidence: 99%

See 2 more Smart Citations

Tuneable quantum spin Hall states in confined 1T' transition metal dichalcogenides

Das

Sen

Mahapatra

2020

Sci Rep

View full text Add to dashboard Cite

Investigation of quantum spin Hall states in 1T' phase of the monolayer transition metal dichalcogenides has recently attracted the attention for its potential in nanoelectronic applications. While most of the theoretical findings in this regard deal with infinitely periodic crystal structures, here we employ density functional theory calculations and k p. Hamiltonian based continuum model to unveil the bandgap opening in the edge-state spectrum of finite width molybdenum disulphide, molybdenum diselenide, tungsten disulphide and tungsten diselenide. We show that the application of a perpendicular electric field simultaneously modulates the band gaps of bulk and edge-states. We further observe that tungsten diselenide undergoes a semi-metallic intermediate state during the phase transition from topological to normal insulator. The tuneable edge conductance, as obtained from the Landauer-Büttiker formalism, exhibits a monotonous increasing trend with applied electric field for deca-nanometer molybdenum disulphide, whereas the trend is opposite for other cases.Topological insulators (TI) 1-4 have emerged as a relatively new quantum state of matter, characterized by gapped (insulating) bulk states and gapless (highly conducting) edge/surface states according to the bulk-boundary correspondence. The 'topological' attribute in this context is the nontrivial topology of the bulk bands spanned by their characteristic electron wavefunctions. Since this nontrivial topology is a characteristic of the gapped energy states, in order to flip the topology across the interface, either the energy gap has to be closed or the symmetry property protecting the edge/surface states has to be broken. Appearance of gapless edge (2D) or surface (3D) states at the interface of a TI and a normal insulator (NI) or vacuum is thus the most fundamental property of a topologically nontrivial phase.Quantum spin Hall insulators (QSHI) or 2D TIs, as originally proposed by Kane and Mele 5,6 , features spin-polarized 'helical' edge states with opposite momentum on each side of the sample to form a Kramer's pair. According to Kane and Mele 5 , graphene was predicted to be a QSHI with a finite gap opening at Dirac point due to spin-orbit coupling (SOC). Unfortunately, very weak SOC in graphene rendered it impossible to experimentally verify their prediction. However, in 2006, the existence of quantum spin Hall (QSH) state was theoretically predicted by Bernevig, Hughes and Zhang (BHZ) 7 and later experimentally demonstrated by König et al. 8 for HgTe/CdTe quantum wells. Thenceforth several other 2D TI materials have been reported such as InAs/GaSb 9,10 quantum wells, bismuthene 11,12 , functionalized Bi/Sb films 13 , monolayer BiX/SbX (X = H, F, Cl and Br) 14 , 2D bismuth arsenic (BiAs) 15 , arsenene 16 , arsenene oxide 17 , monolayer AsSb 18 , phosphorene 19 , silicon-based chalcogenide (Si 2 Te 2 ) 20 , 2D transition-metal halides 21 , monolayer ZrTe 5 and HfTe 5 22 , Cu 2 Te and Ag 2 Te 23 , silicene 24,25 , germanene 26,27 , 2D SiGe 28 , stanene 2...

show abstract

Section: Investigation Of Quantum Spin Hall States In 1t' Phase Of Thmentioning

confidence: 85%

Section: Investigation Of Quantum Spin Hall States In 1t' Phase Of Thmentioning

confidence: 99%

Section: Development Of Kpmentioning

confidence: 99%

See 1 more Smart Citation

Tuneable quantum spin Hall states in confined 1T' transition metal dichalcogenides

Das

Sen

Mahapatra

2020

Sci Rep

View full text Add to dashboard Cite

show abstract

“…v1 ky d4, d5 0 TABLE II. Coefficients of the BHZ Hamiltonian for MX2 family near the Γ0-point [44,45]. m d,p x,y are the effective masses of d and p-bands along different directions, respectively, v1,2 are the velocities and δ is the value of the band inversion.…”

Section: Orbital Currentmentioning

confidence: 99%

“…( 1). [44,45] In k • p approximation, the coefficients of the Hamiltonian are given in Table II. In MoS 2 , the effective masses for p x (p y )orbitals are [42] 17) and performing the integral, for the light frequency equal to the band gap at Γ 0 -point (Ω = 2|δ|), the order of magnitude estimation of the orbital current density is J orb ≈ 10 22 m −1 s −1 .…”

Section: Orbital Currentmentioning

confidence: 99%

Nonlinear orbital response across topological phase transition in centrosymmetric materials

Davydova,

Serbyn,

Ishizuka

2021

Preprint

View full text Add to dashboard Cite

Nonlinear optical responses are often used as a probe for studying electronic properties of materials. For topological materials, studies so far focused on the photogalvanic electric current, which requires breaking inversion symmetry. In this work we present a theory of orbital current response in inversion-symmetric topological insulators. We find a symmetry-allowed orbital current response that occurs in centrosymmetric materials under illumination by linearly polarized light. The sign of the dc nonlinear conductivity reflects the Z2 index and the conductivity changes sign at the transition between trivial and topological insulator phases. We derive an expression for the nonlinear orbital photocurrent for a general class of models with two doubly degenerate bands, and discuss its specific applications in the cases of the Bernevig-Hughes-Zhang model and the 1T' phase of transition metal dichalcogenides. Experimental setups for observation of the orbital current are also discussed.

show abstract

Controllable Phase Stabilities in Transition Metal Dichalcogenides through Curvature Engineering: First‐Principles Calculations and Continuum Prediction

Ouyang

Song

2018

Advcd Theory and Sims

View full text Add to dashboard Cite

A controllable phase transition between the semiconducting 2H phase and metallic/semimetallic T (1T, 1T , and 1T ) isomorphs provides an effective route to tune and even switch physical and electronic properties within 2D transition metal dichalcogenides (TMDs). In this study, the feasibility of curvature engineering in manipulating the structural phase is investigated employing first-principles density functional theory (DFT) calculations and continuum mechanics analysis. With WSe 2 and MoTe 2 as TMD representatives, it is found that bending deformation can not only energetically induce 2H → T (1T, 1T , or 1T ) phase transformation, but also kinetically facilitate the phase transition by lowering transition activation barriers. Moreover, a phase stability diagram is constructed which suggests ways of achieving both uniformly 2H → T phase transition and programming printing of T phases in 2H-TMD membranes. The theoretical results not only suggest a new feasible experimental design strategy of phase engineering, but also sheds light on novel device design with the patterning of T phases on the 2H-TMD membrane.The fascinating physical and chemical properties of the atomically thin VI transition metal dichalcogenide (TMD), a material consisting of two layers of chalcogenide atoms sandwiching one layer of VI transition metal atoms in between, has inspired numerous research studies toward ultra-high light absorption and emission, [1] nanoscale piezoelectric behaviors, [2][3][4][5] and extraordinary valleytronics effects, [2,6,7] showing great promise in numerous applications, such as solar energy, [8][9][10][11][12][13][14] illumination, [11,[14][15][16][17] nano power generator, [2] and valleytronics devices. [6,7,14] Recently, the TMD family attracts further attention because of polymorphism. As shown by many studies, [7,[18][19][20][21] besides the normal octahedral 2H phase, TMDs may assume the form of

show abstract

Assessment of performance potential of MoS2-based topological insulator field-effect transistors

Cited by 12 publications

References 19 publications

Tuneable quantum spin Hall states in confined 1T' transition metal dichalcogenides

Tuneable quantum spin Hall states in confined 1T' transition metal dichalcogenides

Nonlinear orbital response across topological phase transition in centrosymmetric materials

Controllable Phase Stabilities in Transition Metal Dichalcogenides through Curvature Engineering: First‐Principles Calculations and Continuum Prediction

Contact Info

Product

Resources

About