Image Gallery






fascination, issue 12, pp 8, 2013






SuperSTEM 2:


MAADF image of grain boundary in Ba6-3xNd8+2xTi18O54 (BNT)

BNT is a highly important material in mobile phone communication where it is used as resonator/filter in base stations. Adjusting the material properties of this material by varying composition necessitates a detailed understanding of the atomic structure and changes with composition. Atomic resolution imaging allows exact atomic positions to be determined while spatially resolved, atomic resolution EELS measurements give access to the elemental distribution at lattice positions.










SuperSTEM1:

Ripples in suspended Graphene

Spatial frequency filtered HAADF image to show ripples in suspended graphene. Black ‘beads’ are the centres of 'benzene' rings. The bead-strings gave a separation of 0.21 nm, the colour coding is chosen so that the atoms on tops and in throughsof ripples appear yellow and in the flanks bluish. The ripple amplitude is ~0.5 nm and their ‘wavelength’ ~5 nm









SuperSTEM1:

Suspended Graphene with 'dislocation' dipole

Atomic structure of suspended mono-layer graphene, containing a separated ‘dislocation’ dipole, which consists of a shuffle (bottom) and a glide (top) segment. The model structure is overlaid. These dipoles have been predicted by theory. In contrast to semiconductors, where the shuffle segment in sessile and the glide segment is mobile, in graphene the shuffle segment is the mobile, ‘gliding’ segment; lattice resolution HAADF image, low-pass filtered





SuperSTEM1:

Suspended Graphene

Atomic structure of suspended graphene, one mono-atomic layer of graphite (just like chicken wire-see ball and stick model), incorporating carbon ad-atoms on C-C bonds and a vacancy; lattice resolution HAADF, low-pass filtered






SuperSTEM2:

SmartScan

Using a customized STEM EELS acquisition technique it is possible to reduce beam damage by spreading the dose along a rapidly scanned line during spectrum acquisition while keeping the atomic resolution of the UltraSTEM along a line profile. (read more)




SuperSTEM1:

(a) Aberration corrected HAADF High Resolution Scanning Transmission Electron Micrograph (HRSTEM) of a zinc-blende quantum well in a wurtzite segment.
b) An atomistic model of a wurzite/zinc-blende/wurtzite heterostructures along with a schemitcs of the band diagram. The Ga and As atoms have been marked in orange and green, respectively, for the WZ domains, and in red and blue, respectively for the double unit zinc-blende quantum well.











            
SuperSTEM1:

Cellular Structure (stained)


















SuperSTEM2:


Human hepatic ferritin mineral core: Alignment and classification of 750 particles. The tetrad view is still very clear, but less common than in the entire image set. Scale bar is 10nm. Color insert shows single particle 3D reconstruction. (Publication







SuperSTEM 1:

Sum of seven aligned HAADF-STEM images of an intrinsic Si nanowire showing impurities trapped at a twin defect and bulk impurities. 

The unique optical sectioning properties of aberration corrected STEM was used to acquire HAADF images at various depths through a Si nanowire so that the 3D distribution of Au atoms could be determined for the first time.                                                          




SuperSTEM 1:

Gold nanoparticles imaged at 80 kV (left). Small gold clusters on carbon appear less mobile (and thus sharper in the image) at low kV (right).





SuperSTEM2:

Nanotoxicity: what is in the air you breath?

This image shows particles of magnesium oxide captured from the smoke of burning magnesium metal. It was recorded at the SuperSTEM facility at Daresbury Laboratory on an electron microscope that has compensation for the defects in its lenses. It was collected on a digital camera, and has been Fourier filtered to remove artefacts from the camera. The diameter of the field of view is approximately 300nm.

The structure of these particles produced in a simple plume of smoke are a reminder that there is a hidden world beyond our everyday perception. In the past few decades our ability to study and manipulate materials at the "nanometre" scale (a billion times smaller than a metre) has immensely improved. Tailor-made particles of this size are being produced for use in many applications including medical diagnostics and treatments. However, methods to determine the safety of such materials are only beginning to be developed. There is a tremendous potential for such technology, but only if the risks are rigorously assessed.



 website contact: dorothea@superstem.org