4,139 research outputs found
Fano resonance in the nonadiabatic pumped shot noise of a time-dependent potential well
We use the Floquet scattering theory to study the correlation properties of
the nonadiabatic pumped dc current and heat flow through a time-dependent
potential well. Oscillator induced quasibound states of electrons can transit
to the Floquet states leading to resonant tunneling effect. Virtual electron
scattering processes can produce pumped heat flow, pumped shot noise and pumped
heat flow noise, with presence of time and spatial reversal symmetry. When one
of the Floquet levels matches the quasibound level there strikes a "Fano"
resonance
Aligned Graphene Nanoribbons and Crossbars from Unzipped Carbon Nanotubes
Aligned graphene nanoribbon (GNR) arrays were made by unzipping of aligned
single-walled and few-walled carbon nanotube (CNT) arrays. Nanotube unzipping
was achieved by a polymer-protected Ar plasma etching method, and the resulting
nanoribbon array was transferred onto any substrates. Atomic force microscope
(AFM) imaging and Raman mapping on the same CNTs before and after unzipping
confirmed that ~80% of CNTs were opened up to form single layer sub-10 nm GNRs.
Electrical devices made from the GNRs (after annealing in H2 at high
temperature) showed on/off current (Ion/Ioff) ratios up to 103 at room
temperature, suggesting semiconducting nature of the narrow GNRs. Novel GNR-GNR
and GNR-CNT crossbars were fabricated by transferring GNR arrays across GNR and
CNT arrays, respectively. The production of ordered graphene nanoribbon
architectures may allow for large scale integration of GNRs into
nanoelectronics or optoelectronics.Comment: published in Nano Researc
Robust Adaptive Control of a Class of Nonlinear Strict-feedback Discrete-time Systems with Exact Output Tracking
10.1016/j.automatica.2009.07.025Automatica45112537-2545ATCA
Development and construction of China
Libraries in China's higher education institutions have been developing in keeping pace with the flourishing development of China's higher education. This article aims to make an introduction to the construction of China's higher education libraries, especially the recent three decades' achievements since China's reform and opening-up in 1978. In this article, the authors draw a general picture of the development of libraries in China's higher education institutions, covering such eight aspects as management, types and positioning, organizational structure and personnel, expenditure and buildings, reader service, building and sharing of resources as well as automation system.</p
- …