1,419 research outputs found
Symmetry breaking results for problems with exponential growth in the unit disk
We investigate some asymptotic properties of extrema to a two-dimensional
variational problem in the unit disk. Some results about non-radialicity of
solutions are given.Comment: 17 page
Single--peaks for a magnetic Schr\"{o}dinger equation with critic al growth
We prove existence results of complex-valued solutions for a semilinear
Schr\"odinger equation with critical growth under the perturbation of an
external electromagnetic field. Solutions are found via an abstract
perturbation result in critical point theory.Comment: To appea
Global bifurcation of homoclinic solutions of hamiltonian systems
We provide global bifurcation results for a class of nonlinear hamiltonian
systemsComment: 25 page
Multiplicity results for some nonlinear Schroedinger equations with potentials
We prove some multiplicity results for a nonlinear equation of Schroedinger
type with potential function
Compensation of position errors in passivity based teleoperation over packet switched communication networks
Because of the use of scattering based communication channels, passivity based telemanipulation systems can be subject to a steady state position error between master and slave robots. In this paper, we consider the case in which the passive master and slave sides communicate through a packet switched communication channel (e.g. Internet) and we provide a modification of the slave impedance controller for compensating the steady state position error arising in free motion because of packets loss
Semiclassical limit for Schr\"odinger equations with magnetic field and Hartree-type nonlinearities
The semi-classical regime of standing wave solutions of a Schr\"odinger
equation in presence of non-constant electric and magnetic potentials is
studied in the case of non-local nonlinearities of Hartree type. It is show
that there exists a family of solutions having multiple concentration regions
which are located around the minimum points of the electric potential.Comment: 34 page
Observation and Spectroscopy of a Two-Electron Wigner Molecule in an Ultra-Clean Carbon Nanotube
Coulomb interactions can have a decisive effect on the ground state of
electronic systems. The simplest system in which interactions can play an
interesting role is that of two electrons on a string. In the presence of
strong interactions the two electrons are predicted to form a Wigner molecule,
separating to the ends of the string due to their mutual repulsion. This
spatial structure is believed to be clearly imprinted on the energy spectrum,
yet to date a direct measurement of such a spectrum in a controllable
one-dimensional setting is still missing. Here we use an ultra-clean suspended
carbon nanotube to realize this system in a tunable potential. Using tunneling
spectroscopy we measure the excitation spectra of two interacting carriers,
electrons or holes, and identify seven low-energy states characterized by their
spin and isospin quantum numbers. These states fall into two multiplets
according to their exchange symmetries. The formation of a strongly-interacting
Wigner molecule is evident from the small energy splitting measured between the
two multiplets, that is quenched by an order of magnitude compared to the
non-interacting value. Our ability to tune the two-electron state in space and
to study it for both electrons and holes provides an unambiguous demonstration
of the fundamental Wigner molecule state.Comment: SP and FK contributed equally to this wor
Participatory design, beyond the local
This workshop aims at stimulating and opening a debate around the capacity of Participatory Design (PD) and other co-design approaches to deliver outcomes and methodologies that can have an impact and value for reuse well beyond the local context in which they were originally developed. This will be achieved by stimulating the submission of position papers by researchers from the PD community and beyond.These papers will be discussed during the workshop in order to identify challenges, obstacles but also potentials for scaling up PD processes and results from the local to the global.</p
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