Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 6 of 6
Full-Text Articles in Physics
Interaction-Induced Dirac Fermions From Quadratic Band Touching In Bilayer Graphene, Sumiran Pujari, Thomas C. Lang, Ganpathy Murthy, Ribhu K. Kaul
Interaction-Induced Dirac Fermions From Quadratic Band Touching In Bilayer Graphene, Sumiran Pujari, Thomas C. Lang, Ganpathy Murthy, Ribhu K. Kaul
Physics and Astronomy Faculty Publications
We revisit the effect of local interactions on the quadratic band touching (QBT) of the Bernal honeycomb bilayer model using renormalization group (RG) arguments and quantum Monte Carlo (QMC) simulations. We present a RG argument which predicts, contrary to previous studies, that weak interactions do not flow to strong coupling even if the free dispersion has a QBT. Instead, they generate a linear term in the dispersion, which causes the interactions to flow back to weak coupling. Consistent with this RG scenario, in unbiased QMC simulations of the Hubbard model we find compelling evidence that antiferromagnetism turns on at a …
Crystallographically-Oriented Carbon Nanotubes Grown On Few-Layer Graphene Films, Douglas R. Strachan, David P. Hunley
Crystallographically-Oriented Carbon Nanotubes Grown On Few-Layer Graphene Films, Douglas R. Strachan, David P. Hunley
Physics and Astronomy Faculty Patents
A thermal and electrical conducting apparatus includes a few-layer graphene film having a thickness D where D≦1.5 nm and a plurality of carbon nanotubes crystallographically aligned with the few-layer graphene film.
Crystallographically-Oriented Carbon Nanotubes Grown On Few-Layer Graphene Films, David P. Hunley, Douglas R. Strachan
Crystallographically-Oriented Carbon Nanotubes Grown On Few-Layer Graphene Films, David P. Hunley, Douglas R. Strachan
Physics and Astronomy Faculty Patents
A thermal and electrical conducting apparatus includes a few-layer graphene film having a thickness D where D≦1.5 nm and a plurality of carbon nanotubes crystallographically aligned with the few-layer graphene film.
Emergence Of Helical Edge Conduction In Graphene At The Ν = 0 Quantum Hall State, Pavel Tikhonov, Efrat Shimshoni, H. A. Fertig, Ganpathy Murthy
Emergence Of Helical Edge Conduction In Graphene At The Ν = 0 Quantum Hall State, Pavel Tikhonov, Efrat Shimshoni, H. A. Fertig, Ganpathy Murthy
Physics and Astronomy Faculty Publications
The conductance of graphene subject to a strong, tilted magnetic field exhibits a dramatic change from insulating to conducting behavior with tilt angle, regarded as evidence for the transition from a canted antiferromagnetic (CAF) to a ferromagnetic (FM) ν = 0 quantum Hall state. We develop a theory for the electric transport in this system based on the spin-charge connection, whereby the evolution in the nature of collective spin excitations is reflected in the charge-carrying modes. To this end, we derive an effective field-theoretical description of the low-energy excitations, associated with quantum fluctuations of the spin-valley domain-wall ground-state configuration which …
Collective Bulk And Edge Modes Through The Quantum Phase Transition In Graphene At Ν = 0, Ganpathy Murthy, Efrat Shimshoni, H. A. Fertig
Collective Bulk And Edge Modes Through The Quantum Phase Transition In Graphene At Ν = 0, Ganpathy Murthy, Efrat Shimshoni, H. A. Fertig
Physics and Astronomy Faculty Publications
Undoped graphene in a strong, tilted magnetic field exhibits a radical change in conduction upon changing the tilt angle, which can be attributed to a quantum phase transition from a canted antiferromagnetic (CAF) to a ferromagnetic (FM) bulk state at filling factor ν = 0. This behavior signifies a change in the nature of the collective ground state and excitations across the transition. Using the time-dependent Hartree-Fock approximation, we study the collective neutral (particle-hole) excitations in the two phases, both in the bulk and on the edge of the system. The CAF has gapless neutral modes in the bulk, whereas …
Physical And Electronic Properties Of Nanoscale 2d Materials, Mathias J. Boland
Physical And Electronic Properties Of Nanoscale 2d Materials, Mathias J. Boland
Theses and Dissertations--Physics and Astronomy
There is a great push towards reducing the size scale of both electronic components and machines. Two dimensional materials, such as graphene, are ideal candidates towards this push, as they are naturally atomically thin. In the case of nanoscale machines, the mechanical properties of the material surfaces become increasingly important. The use of laminar materials, such as graphene and MoS2, to modify the surface properties, yet maintain nanoscale topographical features, are very attractive. Towards this goal, we have investigated the surface properties of MoS2 at the nanoscale using Lateral Force Microscopy (LFM). In these investigations, we measure …