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Post, Kirk; Lee, Y. S.; Chapler, B. C.; Schafgans, A. A.; Novak, Mario; Taskin, A. A.; Segawa, Kouji; Goldflam, Michael; Stinson, H. T.; Ando, Yoichi; Basov, D. N.

doi:10.1103/physrevb.91.165202

Cited by 18 publications

(12 citation statements)

References 52 publications

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“…Ren et al reinvestigated the electronic and structural phase diagram to achieve the intrinsic topological insulating state in these compounds and prescribed that the highest resistivity can be realised close to composition Bi 1.5 Sb 0.5 Te 1.7 Se 1.3 [11]. Since then BSTS has been studied by various groups through transport [10,11,[14][15][16][17][18][19] and spectroscopic measurements [18][19][20][21][22].…”

mentioning

confidence: 99%

Prominent metallic surface conduction and the singular magnetic response of topological Dirac fermion in three-dimensional topological insulator Bi1.5Sb0.5Te1.7Se1.3

Dutta

Mandal

2017

Sci Rep

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We report semiconductor to metal-like crossover in the temperature dependence of resistivity (ρ) due to the switching of charge transport from bulk to surface channel in three-dimensional topological insulator Bi1.5Sb0.5Te1.7Se1.3. Unlike earlier studies, a much sharper drop in ρ(T) is observed below the crossover temperature due to the dominant surface conduction. Remarkably, the resistivity of the conducting surface channel follows a rarely observable T 2 dependence at low temperature, as predicted theoretically for a two-dimensional Fermi liquid system. The field dependence of magnetization shows a cusp-like paramagnetic peak in the susceptibility (χ) at zero field over the diamagnetic background. The peak is found to be robust against temperature and χ decays linearly with the field from its zero-field value. This unique behavior of the χ is associated with the spin-momentum locked topological surface state in Bi1.5Sb0.5Te1.7Se1.3. The reconstruction of the surface state with time is clearly reflected through the reduction of the peak height with the age of the sample.

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mentioning

confidence: 99%

Prominent metallic surface conduction and the singular magnetic response of topological Dirac fermion in three-dimensional topological insulator Bi1.5Sb0.5Te1.7Se1.3

Dutta

Mandal

2017

Sci Rep

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“…The infrared and optical response of Bi 2 (Te 1−x Se x ) 3 compounds have been intensively studied in order to characterize their vibrational properties 11 , interband absorption [12][13][14][15][16][17] and free charge carrier properties 14,[18][19][20] . Even the surface states [21][22][23][24] and strong Faraday rotation 25 have been observed by infrared spectroscopy.…”

Section: Introductionmentioning

confidence: 99%

Interband absorption edge in the topological insulators Bi2(Te1−xSex)3

et al. 2017

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We have investigated the optical properties of thin films of topological insulators Bi2Te3, Bi2Se3 and their alloys Bi2(Te1−xSex)3 on BaF2 substrates by a combination of infrared ellipsometry and reflectivity in the energy range from 0.06 to 6.5 eV. For the onset of interband absorption in Bi2Se3, after the correction for the Burstein-Moss effect, we find the value of direct bandgap of 215±10 meV at 10 K. Our data supports the picture that Bi2Se3 has a direct band gap located at the Γ point in the Brillouin zone and that the valence band reaches up to the Dirac point and has the shape of a downward oriented paraboloid, i.e. without a camel-back structure. In Bi2Te3, the onset of strong direct interband absorption at 10 K is at a similar energy of about 200 meV, with a weaker additional feature at about 170 meV. Our data support the recent GW band structure calculations suggesting that the direct interband transition does not occur at the Γ point but near the Z-F line of the Brillouin zone. In the Bi2(Te1−xSex)3 alloy, the energy of the onset of direct interband transitions exhibits a maximum near x = 0.3 (i.e. the composition of Bi2Te2Se), suggesting that the crossover of the direct interband transitions between the two points in the Brillouin zone occurs close to this composition.

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“…In BSTS, the p-and n-type defects compensate each other to reduce bulk conductivity. [24] We propose a PCH composed of two 1D PCs constructed out of layers of materials A and B, alternately stacked with respective layers thicknesses d a and d b . The PCH is sandwiched between topological insulator layers (T 1 , T 2 ), as shown in Figure 1.…”

Section: Proposed Geometry and Theoretical Modelingmentioning

confidence: 99%

Dual‐Band Absorption Effect in a Topological‐Insulator‐Based Tamm Plasmon Multilayer System

Meghna

Mathew

2021

Physica Rapid Research Ltrs

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Topological insulator materials have attracted greater attention in recent years due to their conducting surface state and insulating bulk state. The unique surface states in topological insulators offer potential applications in photonics and optoelectronics. Herein, topological insulators' near-infrared plasmonic behavior is utilized to demonstrate a tunable double-mode absorber that shows an electromagnetically induced transparency (EIT)-like effect. A composite structure is formed by sandwiching a photonic crystal heterostructure between topological insulator layers. The transfer matrix method is used to examine the optical response. The evolution of the modes with changes in layer thicknesses, grating period number, and propagating angle is also investigated. The study is further extended to multichannel optical absorption by making changes in the composite structure period, and the resultant absorption spectrum shows a multichannel EIT-like effect.

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Infrared probe of the bulk insulating response inBi2−xSbxTe3−y

Cited by 18 publications

References 52 publications

Prominent metallic surface conduction and the singular magnetic response of topological Dirac fermion in three-dimensional topological insulator Bi1.5Sb0.5Te1.7Se1.3

Prominent metallic surface conduction and the singular magnetic response of topological Dirac fermion in three-dimensional topological insulator Bi1.5Sb0.5Te1.7Se1.3

Interband absorption edge in the topological insulators Bi2(Te1−xSex)3

Dual‐Band Absorption Effect in a Topological‐Insulator‐Based Tamm Plasmon Multilayer System

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