Jun. 20, 2013

Powerful Scanning Transmission Electron Holography Microscope at the University of Victoria Ready ...

The world's most powerful microscope, which resides in a specially constructed room at the University of Victoria (Canada), has now been fully assembled and tested, and has a lineup of scientists and businesses eager to use it. The seven-tonne, 4.5-metre tall Scanning Transmission Electron Holography Microscope (STEHM), the first such microscope of its type in the world, came to the university in parts last year,. A team from Hitachi, which constructed the ultra high-resolution, ultra-stable instrument, spent one year painstakingly assembling the STEHM in a carefully controlled lab in the basement of the Bob Wright Centre.
moreJun. 14, 2013

Photonic Wheels: for Drag Racing at Nano Scale

Optical tweezers will soon be more agile than ever before since light beams can now induce a rolling movement onto a nanoscale object, in addition to pushing it along a surface. Optical tweezers and spanners are about to become more sophisticated. A group of physicists in Germany has just demonstrated, for the first time, the existence of a novel, transverse effect pertaining to light beams used for optical trapping, called photonic wheel.
moreJun. 07, 2013

Self-Organized Gold Honeycomb Structure

The early growth stage and growth evolution to a unique gold (Au) honeycomb nano-network on Si(111)7×7 at room temperature have been studied by direct filled-state and empty-state imaging by scanning tunneling microscopy (STM). The gold honeycomb structure is made up of six triangular gold clusters around the corner hole interconnected to one another in the dimer rows of the Si(111)7×7 substrate. moreJun. 04, 2013

Non-contact AFM: A Chemical Reaction Caught in the Act

When Felix Fischer of the U.S. Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) set out to develop nanostructures made of graphene using a new, controlled approach to chemical reactions, the first result was a surprise: spectacular images of individual carbon atoms and the bonds between them.
moreMay. 06, 2013

Quantum-assisted Nano-imaging of Living Organism

In science, many of the most interesting events occur at a scale far smaller than the unaided human eye can see. Medical researchers might realize a range of breakthroughs if they could look deep inside living biological cells, but existing methods for imaging either lack the desired sensitivity and resolution or require conditions that lead to cell death, such as cryogenic temperatures. Recently, however, a team of Harvard University-led researchers working on DARPA's Quantum-Assisted Sensing and Readout (QuASAR) program demonstrated imaging of magnetic structures inside of living cells. Using equipment operated at room temperature and pressure, the team was able to display detail down to 400 nanometers, which is roughly the size of two measles viruses.
moreApr. 29, 2013

Transmission Electron Microscopy: Imaging Nanoparticles in Action

The macroscopic effects of certain nanoparticles on human health have long been clear to the naked eye. What scientists have lacked is the ability to see the detailed movements of individual particles that give rise to those effects. In a recently published study, scientists at the Virginia Tech Carilion Research Institute invented a technique for imaging nanoparticle dynamics with atomic resolution as these dynamics occur in a liquid environment. The results will allow, for the first time, the imaging of nanoscale processes, such as the engulfment of nanoparticles into cells.
moreApr. 22, 2013

Infrared Images of Single Electrons

Scattering-type near-field optical microscopy (s-SNOM) is a powerful technique to image nano objects. It can be employed in a broad spectral range, namely the complete infrared region spanning from the terahertz range up to the visible range. In this article we describe a system which utilizes a free-electron laser as a spectrally narrow and widely tunable source of infrared radiation. This system was employed to study electrons confined in self-assembled InAs quantum dots. We spatially resolved single quantum dots upon resonant excitation of transitions between discrete energy levels of the confined electrons.
moreApr. 16, 2013

Targeted Subcellular Nanoanalysis

We developed a new approach using cryo-correlative light and scanning transmission electron microscopy allowing analysis of targeted in situ intracellular ions and water measurements at the ultrastructural level within domains identified by examination of specific GFP-tagged proteins [1]. We illustrate the potential of this approach by investigating changes in water and ion content in nuclear domains identified by GFP-tagged proteins in cells stressed by Actinomycin D treatment and controls. moreApr. 11, 2013

High-energy X-rays: Measuring the Structure of Nanomaterials under Extremely High Pressures

A team of researchers has made a major breakthrough in measuring the structure of nanomaterials under extremely high pressures. For the first time, they developed a way to get around the severe distortions of high-energy X-ray beams that are used to image the structure of a gold nanocrystal. The technique, described in Nature Communications, could lead to advancements of new nanomaterials created under high pressures and a greater understanding of what is happening in planetary interiors.
moreApr. 04, 2013

Electron Microscopy: Visualizing Jumping Silicon Atoms in Graphene

Jumping silicon atoms are the stars of an atomic scale ballet featured in a new Nature Communications study from the Department of Energy's Oak Ridge National Laboratory. The ORNL research team documented the atoms' unique behavior by first trapping groups of silicon atoms, known as clusters, in a single-atom-thick sheet of carbon called graphene. The silicon clusters, composed of six atoms, were pinned in place by pores in the graphene sheet, allowing the team to directly image the material with a scanning transmission electron microscope.
more