58,406 research outputs found
Hilbert's 16th Problem for Quadratic Systems. New Methods Based on a Transformation to the Lienard Equation
Fractionally-quadratic transformations which reduce any two-dimensional
quadratic system to the special Lienard equation are introduced. Existence
criteria of cycles are obtained
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Source-specific Fine Particulate Using Spatiotemporal Concentration Fields Developed using Chemical Transport Modelling and Data Assimilation
Radiation-Induced "Zero-Resistance State" and the Photon Assisted Transport
We demonstrate that the radiation induced "zero-resistance state" observed in
a two-dimensional electron gas is a result of the non-trivial structure of the
density of states of the systems and the photon assisted transport. A toy model
of a structureless quantum tunneling junction where the system has oscillatory
density of states catches most of the important features of the experiments. We
present a generalized Kubo-Greenwood conductivity formula for the photon
assisted transport in a general system, and show essentially the same nature of
the transport anomaly in a uniform system.Comment: 4 pages, 3 figures. Please send comment to [email protected]. This
version added a paragraph to discuss the implication of negative conductanc
Transition from Quantum to Classical Information in a Superfluid
Whereas the entropy of any deterministic classical system described by a
principle of least action is zero, one can assign a "quantum information" to
quantum mechanical degree of freedom equal to Hausdorff area of the deviation
from a classical path. This raises the question whether superfluids carry
quantum information. We show that in general the transition from the classical
to quantum behavior depends on the probing length scale, and occurs for
microscopic length scales, except when the interactions between the particles
are very weak. This transition explains why, on macroscopic length scales,
physics is described by classical equations.Comment: 11 pages, 4 figure
Vibration Induced Non-adiabatic Geometric Phase and Energy Uncertainty of Fermions in Graphene
We investigate geometric phase of fermion states under relative vibrations of
two sublattices in graphene by solving time-dependent Sch\"{o}dinger equation
using Floquet scheme. In a period of vibration the fermions acquire different
geometric phases depending on their momenta. There are two regions in the
momentum space: the adiabatic region where the geometric phase can be
approximated by the Berry phase and the chaotic region where the geometric
phase drastically fluctuates in changing parameters. The energy of fermions due
to vibrations shows spikes in the chaotic region. The results suggest a
possible dephasing mechanism which may cause classical-like transport
properties in graphene.Comment: 9 pages, 5 figure
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