Thermal damping of quantum interference patterns of surface-state electrons

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Limited-angle electron tomography (ET) aims to reconstruct 3D shapes from 2D projections of transmission electron microscopy (TEM) within a restricted range and number of tilting angles, but it suffers from the missing-edge problem that causes severe reconstruction artefacts. Deep learning approaches have shown promising results in alleviating these artefacts, yet they typically require large high-quality training datasets with known 3D ground truth, which are difficult to obtain in electron microscopy. To

An apparatus for observing dynamic systems by time-resolved microscopy has an optical microscope including a cryo stage for receiving a cryo sample and maintaining the cryo sample at a cryogenic temperature, a heating system configured to temporarily heat at least a portion of the cryo sample such that the portion of the cryo sample melts to a liquid state, temporarily resides in the liquid state, and then revitrifies, and an image detector associated with the optical microscope for detecting magnified imag

We have recently introduced a novel approach to time-resolved cryo-electron microscopy (cryo-EM) that affords microsecond time resolution. It involves melting a cryo sample with a laser beam to allow dynamics of the embedded particles to occur. Once the laser beam is switched off, the sample revitrifies within just a few microseconds, trapping the particles in their transient configurations, which can subsequently be imaged to obtain a snap shot of the dynamics at this point in time. While we have previousl

Ion Accoustic Wave (IAW) dynamics are usually simulated assuming an isothermal Boltzmann ﬂuid response of the electrons. It has been shown that results from the Boltzmann model may signiﬁcantly diﬀer from cor- responding ones obtained considering the fully kinetic electron dynamics, in particular wrt. the non-linear instability mechanisms of ﬁnite amplitude IAWs [1]. For ZTe /Ti 10 (Z the ionization degree and Te/i the electron/ion temperature), the positive contribution from trapped electrons to the non- l

In this contribution, we study the increase in metalorganic-low pressure chemical vapor deposited (MO-LPCVD) ZnO thin films conductivity by hydrogen plasma post-treatment. We show that this improvement is linked to defect passivation at grain boundaries, decreasing the electron traps density and resulting in the almost complete suppression of the electron scattering at grain boundaries. For a 2 μm thick non-intentionally doped ZnO layer, electron mobility reaches after treatment values close to 60 cm2V-1s-1

Dielectric Barrier Discharge in air at atmospheric pressure

We present results on various post processing techniques to create complex 3-dimensional nanostructures with enhanced capabilities. The starting point for all architectures is a self aligned nanopillar with surrounding circular rim in PMMA. This particular shape is obtained by the energy density distribution of incident and backscattered electrons of e-beam exposure and reflects the dual behavior of PMMA as positive and negative resist. Employing only 1 lithographic step and several batch processing techniq

A detailed structural analysis of the surface supported self-assembly of terphenyl-4,4′′-dicarbonitrile molecules (NC−Ph3−CN) linked by Co adatoms on Ag(111) reveals different surface patterns depending on the constraints applied to the system. Without constraints, i.e., sufficient mobility and absence of space limitations at the surface, extended regular honeycomb nanomeshes are formed. On the basis of high-resolution scanning tunneling microscopy images, an atomistic model is derived showing the crystallo

We propose a new measurement technique to investigate the highly focused light used in optical data storage systems named immersion high resolution interference microscopy (HRIM). This system allows three-dimensional (3D) measurements of the amplitude and phase of light fields in a static scheme. In contrast to scanning techniques, HRIM allows the nondestructive investigation penetrating through the optical disc. We investigated the focusing of light in high-definition digital versatile disc (HD DVD) system

Smart packaging concept has been the driving force for the search of advanced technologies to produce multi-functional micro-scale devices for long years. In this sense, LTCC technology has been recently addressed as the suitable choice for a wide range of applications. In addition to its attractive characteristics for high-frequency applications those have been profited for a long time, it receives a growing attention for sensor applications in the recent years as well. This is due to the easy machinabilit

We develop wear resistant, electrically conducting AFM probes. Here, we describe a new AFM probe made entirely out of tungsten (W). The fabrication involves microfabrication techniques such as surface moulding, thin-film structuring of tungsten and high aspectratio SU-8 patterning. The metallic cantilever and tip are attached to a SU-8 photopolymer body. The free-standing 500-nm-thick cantilevers are obtained by a wafer-through etching. Figure 2 shows a SEM image of the SU-8 body with W cantilevers and a cl

The advent of scanning near-field optical microscopy (SNOM) has augmented at a microscopic level the usefulness of optical spectroscopy in the region between 300 nm and 10 mum. Two-dimensional imaging of chemical constituents makes this a very attractive and powerful new approach. In this paper we show SNOM results obtained in several geometrical configurations on boron clusters in silicon, Li clusters embedded in a LiF sample and BN growth on silicon. We also show some results on the wavelength dependence

Scanning capacitance microscopy and electrostatic force microscopy have been used to characterize commercial semiconductor devices at various stages of the fabrication process. These methods, combined with conventional atomic force microscopy, allow to visualize qualitatively the oxide thickness, the nature of dopants and the exact position of implanted areas. (C) 2002 Elsevier Science Ltd. All rights reserved.

Fatigued state of the Pt-PZT-Pt system is studied by means of low-temperature conduction measurements. It is shown that the conduction in the temperature interval of 100-140 degrees K is determined by the cold field emission of electrons (tunneling conduction mechanism). The Fowler-Nordheim equation describes well the observed current-voltage relations for reasonable values of the system parameters. The conduction measurements in this regime show that the strong fatigue of the switching polarization provoke

We have developed an ultra-stable low temperature scanning tunneling microscope (LTSTM) for application in atomic scale spectroscopy and atom manipulation experiments. The design is based on the Besocke type microscope allowing the installation of the LTSTM within a liquid helium bath (LHe) cryostat in ultra-high-vacuum (UHV). The exclusive use of nonmagnetic materials allows STM-operation in magnetic fields up to 5 T without influencing the measurements. Compared to the frequently used "beetle" type STM th

The electronic states in the conduction and valence bands of quantum wires are studied by means of the effective mass hamiltonian and the Luttinger hamiltonian. The band mixing effects due to the wire geometry are fully taken into account by an accurate finite element solution of the resulting Schrodinger equations. The quantum wire profiles measured by transmission electron microscopy are used. The comparison of theoretical results with photoluminescence excitation spectra of various nanostructures yields

High-resolution angle-resolved photoemission and core-level photoemission measurements were performed on single crystal samples of the quasi-one-dimensional material (TaSe4)(2)I and the cuprate superconductor Bi2Sr2CaCu2O8+x. Resistivity measurements were performed on both materials. X-ray diffraction, transmission electron microscopy (TEM), and AC susceptibility measurements were performed on the cuprate samples. The data indicate that photoemission studies provide key information in understanding the phys

We present new results from the soft X-ray scanning photoemission microscope: MAXIMUM. The microscope is installed at the U41 undulator at the Synchrotron Radiation Center at the University of Wisconsin. The instrument is based on a multilayer-coated Schwarzchild objective, operating at 95 eV, and it has demonstrated spatial resolution better than 0.1 mum and electron energy resolution of 300 meV. We review the design and the implementation of the microscope. We also present recent results as well as a summ

When a light beam impinges on two interacting objects of subwavelength size, a spatially confined electromagnetic field arises in the immediate proximity of the particles. In scanning probe microscopy, short-range forces induced by this electromagnetic near-field change the magnitude of the probe tip-substrate interaction. In this letter we analyse the physical process responsible for these forces in the context of the localized field susceptibility method.

Angle-resolved, synchrotron-radiation photoemission and low-energy electron-diffraction studies of single-crystal Bi2Sr2CaCu2Ox high-temperature superconductors establish that the [100] and [010] directions exhibit quantitatively different structural and electronic properties. Specifically, there is a superlattice modulation in the [010] direction, with superlattice period between 4.7 and 5.2 times the period in the [100] direction. Accompanying this structural difference there is a marked difference in the

Thermal damping of quantum interference patterns of surface-state electrons

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Microsecond melting and revitrification of cryo samples with a correlative light electron microscopy setup

Microsecond melting and revitrification of cryo samples with a correlative light-electron microscopy approach

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