Recent inelastic neutron scattering experiments on (VO)2P2O7 (VOPO) have seen previously unanticipated sharp peaks in the dynamic structure factor in addition to the pair of triplet modes observed earlier. We argue that the additional features are in essence ‘shadows’ of the previously studied features arising due to umklapp scattering, and suggest experimental tests of this proposal. The basic...

We study Umklapp couplings and their renormalisation group flow for electrons in a two-dimensional lattice. It is shown that the effective low energy Hamiltonian involves not only forward scattering, but also considerable non-forward Umklapp scattering, when the electrons fill a substantial fraction of the valence band. The behavior of these couplings under the renormalisation group is studied ...

We study interacting bosons on a lattice in a magnetic field. When the number of flux quanta per plaquette is close to a rational fraction, the low-energy physics is mapped to a multispecies continuum model: bosons in the lowest Landau level where each boson is given an internal degree of freedom, or pseudospin. We find that the interaction potential between the bosons involves terms that do no...

The problem of phonon scattering by strain fields caused by Stone-Wales (SW) defects in graphene is studied in the framework of the deformation potential approach. An explicit form of the phonon mean free path due to phonon-SW scattering is obtained within the Born approximation. The mean free path demonstrates a specific q-dependence varying as q (-3) at low wavevectors and taking a constant v...

(RETRACTED PAPER) The Publisher and Editor retract this article based on the Publication Ethics In this project,Bio-based carbon nanotubes (CNTs) have received considerable research attention due to their comparative advantages of high level stability, simplistic use, low toxicity and overall environmental friendliness. New potentials for improvement in heat transfer applications are presented ...

Umklapp scattering determines the conductivity of clean metals. In typical quasi one-dimensional Fermi liquids with an open Fermi surface, certain pseudo-momenta do not decay by 2-particle collisions even in situations where Umklapp scattering relaxes the momentum of the quasi particles efficiently. Due to this approximate conservation of pseudo-momentum, a certain fraction of the electrical cu...

We examine a two-dimensional Fermi liquid with a Fermi surface which touches the Umklapp surface first at the 4 points (±π/2, ±π/2) as the electron density is increased. Umklapp processes at the 4 patches near (±π/2, ±π/2) lead the renor-malization group equations to scale to strong coupling resembling the behavior of a 2-leg ladder at half-filling. The incompressible character of the fixed poi...

We examine a two-dimensional Fermi liquid with a Fermi surface which touches the Umklapp surface first at the 4 points (±π/2, ±π/2) as the electron density is increased. Umklapp processes at the 4 patches near (±π/2, ±π/2) lead the renor-malization group equations to scale to strong coupling resembling the behavior of a 2-leg ladder at half-filling. The incompressible character of the fixed poi...