Evolution of Topological Surface States in Antimony Ultra-Thin Films

Yao, Guanggeng; Luo, Ziyu; Pan, Feng; Xu, Wentao; Feng, Yuan Ping; Wang, Xuesen

doi:10.1038/srep02010

Cited by 46 publications

(53 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…dI/dV linecuts extracted along these high-symmetry directions (Fig. 9e-f) show QPI modes as intensity peaks that disperse approximately linearly with energy over ∼ 300 mV from the Dirac point, the Γ−M dispersion having been reported previously [52][53][54]. The prominent modes seen in such data sets are labeled as q Γ−M,1 , q Γ−M,2 , and q Γ−K respectively.…”

Section: E Quasiparticle Interference Spectroscopysupporting

confidence: 67%

Momentum-resolved STM studies of Rashba-split surface states on the topological semimetal Sb

Soumyanarayanan

Hoffman

2015

Journal of Electron Spectroscopy and Related Phenomena

View full text Add to dashboard Cite

Topological materials host protected surface states with locked spin and momentum degrees of freedom. The helical Dirac character of the surface states, of tremendous scientific interest, stems from the interplay of the bulk band structure and surface Rashba spin-orbit interaction. The semimetal Sb offers a pristine platform to examine the Rashba origins of the Dirac-like topological surface states. Here we present an overview of our momentum-resolved scanning tunneling spectroscopy studies of Sb, over an extended (300 meV) energy range, revealing several features characteristic of the emergence of the Dirac-like surface states from a conventional Rashba-type parabolic dispersion. Our work provides a conceptual framework to create and investigate tunable Rashba states with topological properties.

show abstract

Section: E Quasiparticle Interference Spectroscopysupporting

confidence: 67%

Momentum-resolved STM studies of Rashba-split surface states on the topological semimetal Sb

Soumyanarayanan

Hoffman

2015

Journal of Electron Spectroscopy and Related Phenomena

View full text Add to dashboard Cite

show abstract

“…[32][33][34][35][36][37][38][39][40] For these As and Sb nanosheets, the corresponding parent bulk materials, i.e. 42 Thus, it is expected that monolayer and few-layered arsenene and antimonene nanosheets could be synthesized as other 2D nanomaterials. 41 Experimentally, ultra-thin Sb films, which are composed of multi-layered Sb sheets, have already been prepared.…”

Section: Introductionmentioning

confidence: 99%

The electronic structures of group-V–group-IV hetero-bilayer structures: a first-principles study

Wang

Ding

2015

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

Recent findings of group-V nanosheets provide new building units for van der Waals hetero-nanostructures. Based on first-principles calculation, we investigate the structural and electronic properties of bilayer hetero-sheets composed of group-V (arsenene/antimonene) and group-IV (graphene/silicene) layers. These hetero-sheets exhibit typical van der Waals features with small binding energies and soft interlayer elastic constants. In the hetero-sheets, the Dirac characteristics of the group-IV layer and the semiconducting feature of the group-V one are well preserved, which causes a Schottky contact at the metal-semiconductor interface. The Schottky barriers are always p-type in the Si-based hetero-sheets, whereas in the C-based ones, the interfacial feature is sensitive to the interlayer distance. A tensile strain would induce a p-type-to-n-type Schottky barrier transition for the As-C hetero-sheet, while a compressive strain can cause a Schottky-to-ohmic contact transition in the Sb-C one. Moreover, due to the inhomogeneous charge redistribution, a sizeable band gap is opened at the Dirac point of the Sb-Si hetero-sheet, which could be linearly modulated by perpendicular strains around the equilibrium site. The versatile electronic structures and tunable interfacial properties enable the group-V-group-IV hetero-bilayer structures to have many potential applications in nano-devices and nano-electronics.

show abstract

“…Two Rashba-type spin-split surface bands on Sb(111), connected to the bulk conduction and the valence bands separately, result in a single Dirac cone within the bulk bandgap of Sb [21][22][23][24][25][26][27][28][29]. Importantly, Sb(111) thin films with a thickness of ≤15 bilayers (BL; with 1 BL = 3.75 Å) can be converted into a 3D TI due to the quantum confinement effect which opens up a positive bandgap for the bulk states [24][25][26]. Such Sb thin films can be obtained by Sb deposition on Si(111) and other substrates, and the electronic states in n-BL Sb(111) thin films with n ≥ 4 have been studied using angle-resolved photoelectron spectroscopy and scanning tunneling spectroscopy (STS) [24,26], which provides direct experimental evidences for the theoretical predications.…”

mentioning

confidence: 99%

“…Importantly, Sb(111) thin films with a thickness of ≤15 bilayers (BL; with 1 BL = 3.75 Å) can be converted into a 3D TI due to the quantum confinement effect which opens up a positive bandgap for the bulk states [24][25][26]. Such Sb thin films can be obtained by Sb deposition on Si(111) and other substrates, and the electronic states in n-BL Sb(111) thin films with n ≥ 4 have been studied using angle-resolved photoelectron spectroscopy and scanning tunneling spectroscopy (STS) [24,26], which provides direct experimental evidences for the theoretical predications. To date, however, the topological properties of n-BL Sb(111) ultrathin films with n < 4 have not been studied experimentally.…”

mentioning

confidence: 99%

“…To date, however, the topological properties of n-BL Sb(111) ultrathin films with n < 4 have not been studied experimentally. On the other hand, the inter-surface coupling of the surface states opens up a gap at the surface Brillouin zone (SBZ) center destroying the Dirac cone [24][25][26]. In this work, we investigate the effects of thickness on the electronic properties of Sb thin films using the first-principles calculations.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Realization of Dirac Cones in Few Bilayer Sb(111) Films by Surface Modification

Hui¹,

Wang²

2016

Nano Online

Self Cite

View full text Add to dashboard Cite

(http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.We report the first-principle study on the recovery and linearization of Dirac cones in the electronic band structures of a few bilayer Sb(111) films ( n-BL Sb) by surface modification. Due to the interaction between the surface states on the two surfaces of a free-standing film, the distorted Dirac cone in n-BL Sb(111) (n < 5) disappears. We demonstrate that the Dirac cone can be restored by functionalizing one surface with certain atoms including H, Ag, and Au, to reduce the inter-surface interaction. We further show that an ideal Dirac cone with linear dispersion of topological surface states near the zone center can be realized by functionalizing both surfaces of the film with oxygen, which enhances spin-orbital coupling. The realization of Dirac cone by surface functionalization shows promise for applications of topologic materials to spintronic devices and their operation in complicated conditions. Keywords: Few bilayer Sb(111) films ; Dirac cones; Surface modification; First-principles calculations BackgroundIn solid-state materials, the modification of electronic states (including spin states) at the interface and on the surface can strongly affect the electronic and magnetic properties of materials. By engineering the interfaces and surfaces of materials based on such modification, devices with versatile functions can be realized [1]. In recent years, a new class of materials, topological insulators (TIs) [2][3][4][5][6][7][8][9][10][11][12][13][14][15], has attracted extensive attention in condensed-matter physics and materials science. TIs in two or three dimensions (2D or 3D) have a nontrivial band order and a bandgap, often generated by the spin-orbit coupling (SOC) effect [16][17][18]. The boundaries (surfaces and interfaces in 3D or edges in 2D) of a TI have gapless states that are protected by time-reversal symmetry. The boundary states of a TI lead to the formation of robust conducting channels with properties that are distinguished from any other low-dimensional systems [18]. These states are predicted to have special properties, such as supporting dissipationless spin currents that may have potential applications in spintronics and quantum computation. The topological surface states can also play a vital role in facilitating surface reactions by serving as an effective electron bath, which may provide new design of heterogeneous catalysts [19]. TIs have also shown promise for thermoelectric applications [20].The TIs discovered so far include simple semimetals (Sb and Bi) [ 4,[21][22][23][24][25][26][27][28][29], alloys (Bi1 − xSbx) [4,16], binary compounds (HgTe, Bi2Se3, Sb2Te3, and Bi2Te3) [4-10, 20, 30-36], and ternary semiconducting Heusler compounds [12][13][14]. As a simple elemental TI, semimetal Sb has t...

show abstract

Evolution of Topological Surface States in Antimony Ultra-Thin Films

Cited by 46 publications

References 38 publications

Momentum-resolved STM studies of Rashba-split surface states on the topological semimetal Sb

Momentum-resolved STM studies of Rashba-split surface states on the topological semimetal Sb

The electronic structures of group-V–group-IV hetero-bilayer structures: a first-principles study

Realization of Dirac Cones in Few Bilayer Sb(111) Films by Surface Modification

Contact Info

Product

Resources

About