Subsequent experiments including our own have demonstrated in SmB6 the metallic surface state and its consistency with the topological picture. Math . II. [1 . 2 Institute for Theoretical Physics and Astrophysics, Wrzburg University, Am Hubland, 97074 Wrzburg,Germany.

In contrast, for gapless surface states, a Berry phase always leads to weak anti-localization and an associated negative mag- Yoshio Kuramoto. This ends up being the result of the Shubnikov-de Haas Effect. Weak anti-localization enhances the conductivity and weak localization suppresses the conductivity with decreasing temperature at very low temperatures. Theor. disordered electron system. Details of crystal growth and various physical properties including high linear magneto resistance are already reported by some of us. Quantitative analysis of the weak antilocalization (WAL) effect of topological surface states in topological insulators is of tremendous importance. We present a magnetotransport study of the Dirac electrons of this compound in the quantum diffusion regime. Bibliographic Details; Author: Wang, Jiannong : Issue Date: 2010: Conference: Hong Kong Forum of Physics 2010: Novel Quantum States and Methods, University of Hong Kong, 17-19 December 2010 . CITED BY Abstract Weak localization and weak anti-localization are quantum interference effects in quantum transport in a disor- dered electron system.

Cross-over from weak anti-localization to localization was also observed in Fe-doped Bi 2 Se 3 nanoribbons . We will discuss the important role of bulk The surface of a three-dimensional (3D) topological insulator is conducting and the topologically nontrivial nature of the Angle-resolved photoemission . Weak anti-localization enhances the conductivity and weak. (a) The change of sheet magnetoconductance plotted in the perpendicular magnetic field component of the magnetic field, Bsin, at 1.9 K. The only. Topological insulators, a new quantum state of matter, create exciting opportunities for studying topological quantum physics and for exploring spintronic applications due to their gapless helical metallic surface states. have sparked worldwide interest owing to their novel physical properties and potential applications in the field of spintronics 1 . Topologically nontrivial: 0 if the surface does encircle the origin. The diagrams for the weak (anti-)localization conductivity of Dirac fermions. Awana1,2* 1CSIR -National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi 110012, India 2Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India Abstract We report, an experimental evidence of surface states (SS) driven magneto-transport in The weak anti-localization effect was dominated by a single two-dimensional channel over two decades of thickness. Anti-Localization (WAL) to Weak Localization (WL) in Cobalt-and Manganese-Doped Bi0.94Sb0.06 Topological Insulator Nanoparticles Localization properties of the doped Z_2-topological insulator are studied by weak localization theory. The U.S. Department of Energy's Office of Scientific and Technical Information DOI: 10.1103/PHYSREVB.86.075102 Corpus ID: 124821444; Weak localization bulk state in a topological insulator Bi2Te3film @article{Zhang2012WeakLB, title={Weak localization bulk state in a topological insulator Bi2Te3film}, author={H. B. Zhang and H. L. Yu and Dinghua Bao and Shunbo Li and C. X. Wang and Guang Yang}, journal={Physical Review B}, year={2012}, volume={86} } Topological insulators, a new quantum state of matter, create exciting opportunities for studying topological quantum physics and for exploring spintronic applications due to their gapless helical metallic surface states. The transition from weak localization to weak anti-localization demonstrates a gap opening at the Dirac point of the surface states in the quantum diffusive regime. We found that at high fields, the magnetoresistance of many samples would oscillate slightly. Our research proves the possibility of building artifical 3D Dirac and Weyl semimetallic structures by means of "van-der-Waals LEGO". The spin-momentum locking property of the TI surface electrons has been probed by optically pumping the TI surface electrons with circularly polarized light and measuring the subsequent current direction . Topological insulators, a new quantum state of matter, create exciting opportunities for . They are basically known for their unique electronic properties of their surface. .1 Introduction The discovery of topological insulators(TIs) is one of the recent . We show that the localization property is closely related to the magnetization of the sample, and the complex crossover is due to the transformation of Bi 2 Se 3 from a topological insulator to a topologically trivial dilute magnetic semiconductor driven by magnetic impurities. He proposed topological Anderson insulator, theory of weak-localization and anti-localization in topological insulators, resonant spin Hall effect and theory of phase separation in colossal magnetoresistive (CMR) materials. In this work, we successfully synthesize PbTe nanowires via the chemical vapor deposition method and demonstrate the existence of topological surface states by . Here we present the magneto-transport properties of our high quality single crystalline Y(Lu)PtBi Heusler topological insulators, which belong to a group of noncentrosymmetric superconductor with . in topological insulator (TI) thin lms of (Bi 0.57 Sb 0.43) 2 Te 3 below six quintuple layers through transport and scanning tunneling spectroscopy measurements. . The transition from weak localization to weak anti-localization demonstrates a gap opening at the Dirac point of the surface states in the quantum diffusive regime. 2D quantum spin Hall insulator - Z 2 topological invariant - Edge states - HgCdTe quantum wells, expts III. Phys. Impurity effect on weak anti-localization in topological insulator Bi2Te3 . Weak (anti-)localization in doped Z_2-topological insulator. CITED BY Abstract Weak localization and weak anti-localization are quantum interference effects in quantum transport in a disor- dered electron system. Gauge transformation on the equator: A N ( h) = A S ( h) d . TKNN number: = 1 2 d A. counts how many times the closed surface encircles the origin. In topological insulators, one expects weak antilocalization (WAL) in the presence of scalar disorder [133,138,139]. We show that a number of transport properties in topological insulator (TI) Bi2Se3 exhibit striking thickness-dependences over a range of up to five orders of thickness (3 nm - 170 mu m). The measured weak anti-localization effect agrees well with the Hikami-Larkin-Nagaoka model and the extracted phase coherent length shows a power-law dependence with temperature (l(phi) similar to T-0.44), indicating the presence of the surface states. hree-dimensional (3d) topological insulators (tis) are distinct materials featuring bulk insulting states and unique massless dirac fermions in the surface state.13in particular, the spins of electrons in these states are tightly locked to their momentums due to the strong spinorbit coupling, and thus backscattering in the dirac fermions by . Weak anti-localization enhances the conductivity and weak localization suppresses the conductivity with decreasing temperature at very low temperatures. He proved existence of antiferromagnetic long-range order and off-diagonal long-range order in itinerant electron systems. Topological insulators are new kind of Dirac materials that possess bulk insulating and surface conducting behavior. sample, and the complex crossover is due to the transformation of Bi2Se3 from a topological insulator to a topologically trivial dilute magnetic semiconductor driven by magnetic impurities. Authors: Garate, Ion; Glazman, Leonid Publication Date: 2012-07-01 NSF-PAR ID: 10004419 Journal Name: Physical Review B Volume: 86 Issue: 3 ISSN: 1098-0121 Publisher: American Physical Society Weak (anti-)localization phenomena can, therefore, serve as a probe of the types of Dirac fermions present in topological semimetals. Discovery of a weak topological insulator BiSe. The transition from weak localization to weak anti-localization demonstrates a gap opening at the Dirac point of the surface states in the quantum diffusive regime. Topological insulators (TI) are an exciting, new topic in condensed matter physics. We study magneto-transport . Weak anti-localization (WAL) effect in BST crystal. Weak anti-localization enhances the conductivity and weak localization suppresses the conductivity with decreasing temperature at very low temperatures.

The disordered Kane-Mele model for graphene is taken as a prototype, and analyzed with attention to effects of the topological mass term, inter-valley scattering, and the Rashba spin-orbit interaction. Weak localization and weak anti-localization are quantum interference effects in quantum transport in a disor- dered electron system. Structure and . Quantum transport in topological insulators: Weak Anti-localization & Electron-electron interaction Hai-Zhou Lu () Department of Physics The University of Hong Kong. The effect can give rise to positive low-field magnetoconductivity at low temperatures19-22. This work demonstrates an effective way to manipulate the magneto-transport properties of the topological insulators by rare-earth element doping. Weak anti-localization and quantum oscillations of surface states in topological insulator BiSeTe. 1 Surface states induced weak anti-localization effect in Bi 0.85 Sb 0.15 topological single crystal Yogesh Kumar1,2 and V.P.S. PDF - Topological insulators, a new quantum state of matter, create exciting opportunities for studying topological quantum physics and for exploring spintronic applications due to their gapless helical metallic surface states. Different from conventional topological insulators (TIs), protection of the surface states comes from point-group symmetry instead of time-reversal symmetry in TIs. In this work, we successfully synthesize PbTe nanowires via the chemical vapor deposition method and demonstrate the existence of topological surface states by . The transition from weak localization to weak anti-localization demonstrates a gap opening at the Dirac point of the surface states in the quantum diffusive regime. sample, and the complex crossover is due to the transformation of Bi2Se3 from a topological insulator to a topologically trivial dilute magnetic semiconductor driven by magnetic impurities. Weak localization and weak anti-localization are quantum interference effects in quantum transport in a disordered electron system. This work demonstrates an effective way to manipulate the magneto-transport properties of the topological insulators by rare-earth element doping. By effective tuning the Fermi level via gate-voltage control, we unveil a striking competition between weak localization and weak antilocalization at low magnetic fields in nonmagnetic ultrathin films, possibly owing to the change of the net Berry phase. Topological crystalline insulators (TCIs) are a subclass of topological materials that possess conducting surface and edge states due to band inversion at locations of high crystal symmetry in the Brillouin zone. Weak localization and weak anti-localization are quantum interference effects in quantum transport in a disordered electron system. . Topological Insulators.

We report the magneto-conductivity analysis at different temperatures under magnetic field of up to 5Tesla of a well characterized Bi2Te3 crystal. 6.1.2 Weak anti-localization in topological insulator thin films in multichannel limit- Two-dimensional weak anti-localization in Bi2Te3 thin film grown on Si(111 . The 3D topological insulators (TIs) have an insulating bulk but momentum spin-coupled metallic surface states stemming from band inversion due to strong spin-orbit interaction, whose existence is guaranteed by the topology of the band structure of the . Topological insulators, a new quantum state of matter, create exciting opportunities for studying topological quantum physics and for exploring spintronic applications due to their gapless helical metallic surface states. Anti-Localization (WAL) to Weak Localization (WL) in Cobalt-and Manganese-Doped Bi0.94Sb0.06 Topological Insulator Nanoparticles Weak anti-localization enhances the conductivity and weak localization suppresses the conductivity with decreasing temperature at very low temperatures. Scientific . Au thin films, Low-Field Weak Anti-Localization also manifested itself in nearly every trial we did. An elaborate thickness, temperature and magnetic field dependence of transport data indicates a transition from coupled, partially coupled and fully . Weak localization and Weak anti-localization Hikami, Larkin, and Nagaoka Prog. Localization properties of the doped Z_2-topological insulator are studied by weak localization theory. SPIE 9167 . Topological crystalline insulators (TCIs) have attracted worldwide interest since their theoretical predication and have created exciting opportunities for studying topological quantum physics and for exploring spintronic applications. The measured weak anti-localization effect agrees well with the Hikami-Larkin-Nagaoka model and the extracted phase . DOI: 10.1103/PHYSREVB.86.075102 Corpus ID: 124821444; Weak localization bulk state in a topological insulator Bi2Te3film @article{Zhang2012WeakLB, title={Weak localization bulk state in a topological insulator Bi2Te3film}, author={H. B. Zhang and H. L. Yu and Dinghua Bao and Shunbo Li and C. X. Wang and Guang Yang}, journal={Physical Review B}, year={2012}, volume={86} } Additionally, we have carried outmagneto-transport measurements on single crystal akes as well as thin lms of BiSe, whichexhibit clear signatures of weak anti-localization at low temperatures, consistent with the prop-erties of topological insulators. Additionally, time-reversal symmetry can be . A topological insulator is a material that is electrically insulating in the bulk while possessing highly conductive and spin-polarized massless Dirac surface states that are protected against disorder by time-reversal symmetry, allowing for near dissipationless transport of spin on the surface. Phys Rev B, 2009.

proximity to a ferromagnetic insulator16-18. In this work, we report the weak anti-localization (WAL) effect and Shubnikov-de Haas (SdH) oscillations originated from the surface states of PbTe nanowires. A gap opened for the surface states by breaking time reversal symmetry in topological insulators is anticipated to host many novel physics 1,2,3,4,5,6,7,8.Experimentally, the gap may be realized either by magnetic doping 9,10,11,12,13,14,15, or by magnetic proximity to a ferromagnetic insulator 16,17,18.One of the signatures of the gap openings is the weak localization effect 19. Here, we report the observation of weak anti-localization and quantum oscillations originated from surface states in Bi 2Se 2Te crystals. Further, the transport properties are investigated, which shows thickness dependence of weak anti-localization effect (WAL) in the system and proposed these Bi2Se3/SiO2 thin films as a topological Anderson insulator (TAI). This cusp-like behavior under low field is a signature of weak anti-localization . Using this experience, in a joint theory-experiment effort [2], we have recently been able to extract phase diagrams of topological insulator heterostructures by carefully analyzing their weak anti-localization data. The disordered Kane-Mele model for graphene is taken as a prototype, and analyzed with attention to effects of the topological mass term, inter-valley scattering, and the Rashba spin-orbit interaction. . . We study the weak antilocalization (WAL) effect in topological insulator ${\mathrm{Bi}}_{2}{\mathrm{Te}}_{3}$ thin films at low temperatures. A newly discovered topological insulator Cm (AgxPb1-xSe)5(Bi2S3)3m (m = 2) has a band gap of 0.5 eV, the largest value reported in topological insulators. . In this work, we discuss weak localization and antilocalization of massless Dirac fermions in topological insulators and massive Dirac fermions in Weyl semimetal thin films, taking into account both intrinsic and extrinsic spin-orbit interactions. Comments: 15 Pages Text + Figs: Accepted JMSE: Subjects: Topological insulator materials are a recently discovered electronic phase with unique properties: such as spin-polarized protected surface/edge states akin to gapless Dirac states in Graphene and bulk magneto-electric effects, amongst others. Here, we report the observation of weak anti-localization and quantum oscillations originated from surface states in Bi2Se2Te crystals. 1,2 1. The transition between weak localization and weak anti-localization demonstrates a gap opening at the Dirac point of surface states in the quantum diffusive regime. This work demonstrates an effective way to manipulate the magneto-transport properties of the topological insulators by rare-earth element doping. . In this work, we discuss weak localization and antilocalization of massless Dirac fermions in topological insulators and massive Dirac fermions . . In contrast, our analysis reveals that topological insulators always exhibit weak antilocalization. In this work, we discuss weak localization and antilocalization of massless Dirac fermions in topological insulators and massive Dirac fermions in Weyl semimetal thin films, taking into account both intrinsic and extrinsic spin-orbit interactions. Fig1 SmB6 weak anti localization. Lu and S. Q. Shen, " Weak localization and weak anti-localization in topological insulators," Proc.

Weak antilocalization - - B (T) Magnetoconductivity due to Weak Anti-localization =1/2 for Au film One surface of TI Traditional 2D systems with strong SOC Hoffmann, PRB (1982) e.g. The disordered Kane-Mele model for graphene is taken as a prototype, and analyzed with attention to effects of the topological mass term, . Topologically trivial: = 0 if the surface does not encircle the origin. The sublinear thickness-dependence of . The WAL correction can be affected by the interaction of the surface states with the residual bulk states . Symmetry classes of random ensembles [F. J. Dyson, J. This work demonstrates an effective way to manipulate the quantum . The two-dimensional WAL effect associated with surface carriers is revealed in the tilted magnetic field dependence of magnetoconductance. Topological insulators, a new quantum state of matter, create exciting opportunities for studying topological quantum physics and for exploring spintronic applications due to their gapless helical metallic surface states. The data are consistent with expectations of the different topological states of these films.