Ross D. McDonald

Two-dimensional surface state in the quantum limit of a topological insulator

The edges of graphene-based systems possess unusual electronic properties, originating from the non-trivial topological structure associated with the pseudospinorial character of the electron wavefunctions. These properties, which have no analogue for electrons described by the Schrödinger equation in conventional systems, have led to the prediction of many striking phenomena, such as gate-tunable ferromagnetism and valley-selective transport1, 2, 3. In most cases, however, the predicted phenomena are not expected to survive the strong structural and chemical disorder that unavoidably affects the edges of real graphene devices. Here, we present a theoretical investigation of the intrinsic low-energy states at the edges of electrostatically gapped bilayer graphene, and find that the contribution of edge modes to the linear conductance of realistic devices remains sizable even for highly imperfect edges. This contribution may dominate over that of the bulk for sufficiently clean devices, such as those based on suspended bilayer graphene samples. Our results illustrate the robustness of those phenomena whose origin is [...] LI, Jian, et al. Topological origin of subgap conductance in insulating bilayer graphene. Nature Physics, 2011, vol. 7, no. 1, p. 38-42 DOI : 10.1038/nphys1822

Bulk Fermi surface coexistence with Dirac surface state in Bi2Se3: A comparison of photoemission and Shubnikov-de Haas measurements

Shubnikov-de Haas (SdH) oscillations and angle-resolved photoemission spectroscopy (ARPES) are used to probe the Fermi surface of single crystals of

Bounding the pseudogap with a line of phase transitions in YBa2Cu3O6+δ.

{\text{Bi}}_{2}{\text{Se}}_{3}

Quasiparticle mass enhancement approaching optimal doping in a high-Tc superconductor

. We find that SdH and ARPES probes quantitatively agree on measurements of the effective mass and bulk band dispersion. In high carrier density samples, the two probes also agree in the exact position of the Fermi level

Sliding charge-density wave in manganites

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Strong H...F hydrogen bonds as synthons in polymeric quantum magnets: structural, magnetic, and theoretical characterization of [Cu(HF2)(pyrazine)2]SbF6, [Cu2F(HF)(HF2)(pyrazine)4](SbF6)2, and [CuAg(H3F4)(pyrazine)5](SbF6)2.

, but for lower carrier density samples discrepancies emerge in the position of

Realization of a three-dimensional spin–anisotropic harmonic honeycomb iridate

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Localized 5f electrons in superconducting PuCoIn5: consequences for superconductivity in PuCoGa5

. In particular, SdH reveals a bulk three-dimensional Fermi surface for samples with carrier densities as low as

Experimentally determining the exchange parameters of quasi-two-dimensional Heisenberg magnets

{10}^{17}\text{ }{\text{cm}}^{\ensuremath{-}3}

Quantum oscillations in the parent pnictide BaFe2As2: Itinerant electrons in the reconstructed state

. We suggest a simple mechanism to explain these differences and discuss consequences for existing and future transport studies of topological insulators.