14,197 research outputs found
Symplectic Schemes for Birkhoffian System
A universal symplectic structure for a Newtonian system including
nonconservative cases can be constructed in the framework of Birkhoffian
generalization of Hamiltonian mechanics. In this paper the symplectic geometry
structure of Birkhoffian system is discussed, then the symplecticity of
Birkhoffian phase flow is presented. Based on these properties we give a way to
construct symplectic schemes for Birkhoffian system by using the generating
function method
Anisotropic intrinsic lattice thermal conductivity of phosphorene from first principles
Phosphorene, the single layer counterpart of black phosphorus, is a novel
two-dimensional semiconductor with high carrier mobility and a large
fundamental direct band gap, which has attracted tremendous interest recently.
Its potential applications in nano-electronics and thermoelectrics call for a
fundamental study of the phonon transport. Here, we calculate the intrinsic
lattice thermal conductivity of phosphorene by solving the phonon Boltzmann
transport equation (BTE) based on first-principles calculations. The thermal
conductivity of phosphorene at is
(zigzag) and
(armchair), showing an obvious anisotropy along different directions. The
calculated thermal conductivity fits perfectly to the inverse relation with
temperature when the temperature is higher than Debye temperature (). In comparison to graphene, the minor contribution around
of the ZA mode is responsible for the low thermal conductivity of
phosphorene. In addition, the representative mean free path (MFP), a critical
size for phonon transport, is also obtained.Comment: 5 pages and 6 figures, Supplemental Material available as
http://www.rsc.org/suppdata/cp/c4/c4cp04858j/c4cp04858j1.pd
Width of the confinement-induced resonance in a quasi-one-dimensional trap with transverse anisotropy
We theoretically study the width of the s-wave confinement-induced resonance
(CIR) in quasi-one-dimensional atomic gases under tunable transversely
anisotropic confinement. We find that the width of the CIR can be tuned by
varying the transverse anisotropy. The change in the width of the CIR can
manifest itself in the position of the discontinuity in the interaction energy
density, which can be probed experimentally.Comment: 6 pages, 3 figures, update references, published versio
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