scholarly journals Formation of Ordered Nanostructures of Target Geometry Using Photo-Induced Volume Charge

2021 ◽  
Vol 19 (1) ◽  
2020 ◽  
Vol 9 (1-2) ◽  
pp. 11-39 ◽  
Author(s):  
Stephan Gräf

AbstractThe use of ultra-short pulsed lasers enables the fabrication of laser-induced periodic surface structures (LIPSS) on various materials following a single-step, direct-writing technique. These specific, well-ordered nanostructures with periodicities in the order of the utilised laser wavelength facilitate the engineering of surfaces with functional properties. This review paper discusses the physical background of LIPSS formation on substrates with different material properties. Using the examples of structural colours, specific wetting states and the reduction of friction and wear, this work presents experimental approaches that allow to deliberately influence the LIPSS formation process and thus tailor the surface properties. Finally, the review concludes with some future developments and perspectives related to forthcoming applications of LIPSS-based surfaces are discussed.


2013 ◽  
pp. 385-417
Author(s):  
Jonas Weickert ◽  
Lukas Schmidt-Mende

Author(s):  
Jing Zhang ◽  
Ru Wang ◽  
Zhiyuan Luo ◽  
Dongmei Jia ◽  
Haoming Chen ◽  
...  

Enzyme proteins are nanometer-sized molecules with a three-dimensional structure that can be manipulated and assembled into highly ordered nanostructures, which allows access to advanced biological materials. Here, genetically-encoded nonstandard amino...


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Francisco Javier Plascencia Jauregui ◽  
Agustín Santiago Medina Vazquez ◽  
Edwin Christian Becerra Alvarez ◽  
José Manuel Arce Zavala ◽  
Sandra Fabiola Flores Ruiz

Purpose This study aims to present a mathematical method based on Poisson’s equation to calculate the voltage and volume charge density formed in the substrate under the floating gate area of a multiple-input floating-gate metal-oxide semiconductor metal-oxide semiconductor (MOS) transistor. Design/methodology/approach Based on this method, the authors calculate electric fields and electric potentials from the charges generated when voltages are applied to the control gates (CG). This technique allows us to consider cases when the floating gate has any trapped charge generated during the manufacturing process. Moreover, the authors introduce a mathematical function to describe the potential behavior through the substrate. From the resultant electric field, the authors compute the volume charge density at different depths. Findings The authors generate some three-dimensional graphics to show the volume charge density behavior, which allows us to predict regions in which the volume charge density tends to increase. This will be determined by the voltages on terminals, which reveal the relationship between CG and volume charge density and will allow us to analyze some superior-order phenomena. Originality/value The procedure presented here and based on coordinates has not been reported before, and it is an aid to generate a model of the device and to build simulation tools in an analog design environment.


Author(s):  
S.L. Timchenko ◽  
N.A. Zadorozhny

The experimental research example of electrical characteristics of structurally heterogeneous thinlayer conductors (nickel, copper) at high current density (108--109 А/m2) is shown. This current density in conditions of the samples intensive cooling is sufficient for the process of irreversible, nonthermally activated deformation. The experiment results show that the conducting medium at high current density has essential nonlinearities expressed in nonlinear dependence of the samples electrical resistance from current density. With repeated current treatments of the samples the conductors' electrical resistivity decreases. The number of defects removed from the volume of material as a result of nickel foil treatment by electric current is estimated. It is shown that under conditions of highdensity direct electric current flow in microvolumes of homogeneous and inhomogeneous conducting media a volume charge can appear. The appearance of the volume charge in a conducting medium can be caused by interaction forces during the motion of electrons and ions. Due to the interaction forces between ions and electrons of basic material and impurities, additional local ionization occurs which is realized in nano-volumes of a conductor. In the case of heterogeneous medium, the volume charge depends on the nature of the specific conductivity distribution. In a homogeneous conductor the volume charge is proportional to the square of the current density in the sample


2014 ◽  
Vol 9 (10) ◽  
pp. 2928-2936 ◽  
Author(s):  
Jing Zhang ◽  
Riccardo Marega ◽  
Li-Jun Chen ◽  
Nai-Wei Wu ◽  
Xing-Dong Xu ◽  
...  

Nano LIFE ◽  
2016 ◽  
Vol 06 (03n04) ◽  
pp. 1642007
Author(s):  
Zhili Yao ◽  
Yuan Sun ◽  
Chen Kang

The one-dimensional (1D) self-assembly of [Formula: see text]-electron molecules offers efficient strategies to enhance energy and charge transfer via highly ordered and conductive [Formula: see text] stacking of the chromophores. The chromophore rich nanostructures have great potential to serve as promising candidate materials for optoelectronic devices. However, the design and control of highly ordered nanostructures with multicolored chromophore redox gradients require finely chosen synthetic strategies and a delicate balance of supramolecular interactions. In this paper, we will introduce new strategies focused on self-assembly of nanofibers based on lysine derivatives functionalized with multi colored chromophores.


2014 ◽  
Vol 5 ◽  
pp. 1873-1886 ◽  
Author(s):  
T O Menteş ◽  
G Zamborlini ◽  
A Sala ◽  
A Locatelli

The implementation of imaging techniques with low-energy electrons at synchrotron laboratories allowed for significant advancement in the field of spectromicroscopy. The spectroscopic photoemission and low energy electron microscope, SPELEEM, is a notable example. We summarize the multitechnique capabilities of the SPELEEM instrument, reporting on the instrumental aspects and the latest developments on the technical side. We briefly review applications, which are grouped into two main scientific fields. The first one covers different aspects of graphene physics. In particular, we highlight the recent work on graphene/Ir(100). Here, SPELEEM was employed to monitor the changes in the electronic structure that occur for different film morphologies and during the intercalation of Au. The Au monolayer, which creeps under graphene from the film edges, efficiently decouples the graphene from the substrate lowering the Dirac energy from 0.42 eV to 0.1 eV. The second field combines magnetism studies at the mesoscopic length scale with self-organized systems featuring ordered nanostructures. This example highlights the possibility to monitor growth processes in real time and combine chemical characterization with X-ray magnetic circular dichroism–photoemission electron microscopy (XMCD–PEEM) magnetic imaging by using the variable photon polarization and energy available at the synchrotron source.


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