Contest Winners

Grand Prize Winner, Scientific Merit

Germanium Nanofibers or Jellyfish Tentacles?

Alejandro Perez-Bergquist, "Germanium Nanofibers or Jellyfish Tentacles?"

HAADF STEM image of Ge nanofibers formed by high energy ion irradiation of crystalline Ge. These fibers form by a self-formation process involving the formation and diffusion of atomic vacancies. The study of these fibers helps us better understand ion irradiation effects in materials.

Grand Prize Winner, Artistic Merit

Secondary Grains of Sintered Barium Titanate

Laura Ligeski, "Secondary Grains of Sintered Barium Titanate"

This image is of the surface of a 99.6% pure barium titanate pellet that was sintered in a cold furnance at a temperature of 1300°C for two hours. This image was taken in order to study the difference between primary and secondary grain growth in this material. The faceting of the secondary grains, which was due to anisotropy of solid-vapor surface energy, can be seen in the secondary grains as multicolored stripes. This image also shows that the sintering of the barium titanate was successful because the material has almost all secondary grains with very minimal primary grains.

Category I - Optical and Scanning Electron Microscopy (First - Third Place)

CdTe Quantum Dot UV Light Luminescence

Damien Stonick, "CdTe Quantum Dot UV Light Luminescence"

CdTe colloidal, pyramidal quantum dots are observed under 40x using a UV light source. Two levels of focus were achievable, 1) the physical aggregations of the drop casting, 2) the luminescence of the aggregations. The green luminescence is characteristic of the excitations of the 2nm diameter quantum dots in the solution. The areas of higher concentration have a higher level of luminescence than the areas of lower concentration. The higher areas of concentration also have a more noticeable red shift in the luminescence. This is due either to FRET, as the solution has a dot diameter variation of 0.29nm and the higher concentration provides a higher probability of smaller dot excitations of larger dots –resulting in a red shifted wavelength of emitted light, or the Solvatochromic effect from the polar thioglycolic acid in the solution that acts as a buffer. The strong photoluminescence of the sample indicates possible photovoltaic application.
Sand in the Stars

Richard R. Lunt, "Sand in the Stars"

This image of a N,N’-diphenyl-N,N’-bis(1-naphthyl)-1,1’biphenyl-4,4’’diamine (-NPD) film was taken using an optical microscope with cross-polarizers and a Nomarski filter at 20x magnification (vertical scale of the image is 1.7mm). The variations in color stem from the anisotropic indices of refraction in combination with the rotation of the crystallites with respect to the polarizer configuration. The image highlights important impacts of the growth rate on the nucleation rate and morphology of melt-grown organic semiconductors. It is also emphasizes the high degree of anisotropy common in molecular crystal structures. Such films are currently being investigated for use in organic electronic architectures.
Quartz Vaterite

Qiaona/Joanna Hu, "Quartz Vaterite"

Calcium-carbonate containing solution was prepared by mixing equal amounts 0.002 mol/L of reagent grade NaHCO3 and CaCl2 .2H2O into distilled deionized water (DDW), subsequently acidified by using HCl to adjust the initial pH to 3.4, under which condition the salt solution was undersaturated. Then the pH of the salt solution was increased by diffusing NH3 gas into the solution gradually. The CaCO3 crystals would precipitate when the solution reached the super saturated status with respective to CaCO3. If the diffusion rate of ammonia was high enough at around 0.134g/liter/hour, vaterite, the most unstable polymorph of CaCO3, was the dominant polymorph. Image “vaterite” was taken by Hitachi S3200N SEM at 17 kv after 24 hours, exhibiting the beautiful individual grown vaterite crystals that like 6-petal flowers, illustrating the hexagonal symmetry of vaterite.

Category II - Optical and Scanning Electron Microscopy (First - Third Place)

Ferroelectric Domain Structure of a (001) BFO Thin Film

Christopher Nelson, "Ferroelectric Domain Structure of a (001) BFO Thin Film"

This image depicts via cross section the ferroelectric domain structure of ~200nm [001] oriented BiFeO3 thin film grown on the (110) surface of orthorhombic TbScO3. Diffraction patterns reveal that the BFO film consists of only 2 of the 4 possible ferroelastic variants which is due to the distorted cubic structure of the TbScO3 substrate. The vertical domain walls indicate that the polarization rotates 109 degrees across the boundary. Thus, the film has an alternating out-of-plane polarization and the net polarization is zero. This domain pattern allows the film to avoid the effects of a depolarization field.
Coexistence of multiple surface reconstructions

Lee "Trey" Sears, "Coexistence of multiple surface reconstructions"

This is a 500x500A STM image of an InGaAs alloy that shows the coexistence of a B2(2x4) and a disordered (4x3) on the surface of the sample. Considering only the difference in the surface energy it is surprising that this coexistence is robust across a range of growth conditions and we believed that strain is the reason for the stability of this mixed reconstruction surface.
Left Behind

Michael Katz, "Left Behind"

A palladium nanopartical suspended on the amorphized remains of a lanthanum ferrate (LFO) film. A small amount of Pd was dissolved in the LFO single crystal thin film. During ion milling, a portion of the film amorphized, allowing the Pd to fall out of solution and remetallize. The LFO was grown atop a calcium titanate thin film, itself grown (both by pulsed laser deposition) on a strontium titanate substrate. Pd was deposited on the final surface via vacuum evaporation and was treated to induce dissolution into the oxide.

Category III - Simulated Microstructures as Products of Computational Materials Science (First - Third Place)

Connectivity of Microstructure

Victor Chan, "Connectivity of Microstructure"

The connectivity of a complex microstructure can provide insight into the bulk properties of a material. For example, by understanding the relationship between connectivity and transport phenomena, microstructures can be tailored to provide optimal transport properties in a material. To analyze the connectivity, the microstructure was calibrated to a distance function. This allows us to analyze the connectivity at various distances away from the microstructure/environment interface. The image displays the connectivity where the colors represent different distances from the interface. The yellow represents closer distances and the blue represents farther distances.
Kelvin-Helmholtz Shock Wave

Nick Patterson, "Kelvin-Helmholtz Shock Wave"

The goal of the simulation was to generate Rayleigh-Taylor and/or Kelvin-Helmholtz instabilities on the mock front. The Kelvin-Helmholtz instabilities can best be described as a curling finger or a twirling offshoot of the main body of the material. These instabilities are clearly evident in many places throughout the image.
Whistler’s Mother on a Lipid Membrane Vesicle?

Chloe Funkhouser, "Whistler’s Mother on a Lipid Membrane Vesicle?"

A snapshot of the microstructure of a two-phase lipid membrane vesicle as it evolves to equilibrium. The color indicates the compositional phase, and membrane deformations resulting from the phase separation are also illustrated, where the blue phase prefers to bulge outward while the red phase prefers to bulge inward. The coupling of composition with mechanical properties influences the shapes that domains take as well as the coarsening dynamics. At this particular time, two of the domains resemble the form in the famous James Abbott McNeill Whistler painting entitled ‘Whistler’s Mother’, shown in the corner of the image for reference.

Category IV - Digitally Enhanced or Colorized Images of Microstructures (First - Third Place)

Artificial bone marrow in a 3D microarchitecture

Jungwoo Lee, "Artificial bone marrow in a 3D microarchitecture"

Notch ligands presenting artificial 3D microenvironments were created on inverted colloidal crystal scaffolds utilizing a layer-by-layer molecular assembly technique. Multi-component LBL film substitute the function of stromal cells and successfully supported ex vivo human hematopoietic stem cells proliferation and differentiation. The image shows the development of pre-erythrocytes attaching on the pore surface which might be the result of activated notch signaling. In addition, dendritic-like cells scavenge across ICC pores which vividly captured an in vivo 3D bone marrow microenvironment.
Fracture Wave

Kevin Grossklaus, "Fracture Wave"

This SEM image shows a fracture surface on an InP wafer. The faceted fracture surface looks like a crashing wave, and has been colorized accordingly. In the top right corner of the image a portion of a rough InAs film that was grown on the InP wafer is visible. InP and other III-V semiconductor wafers cleave easily, making them easily dividable into smaller pieces for study, but also making them very susceptible to unwanted cracking and chipping. In this case the fracture surface pictured was produced when the edge of the sample chipped during preparation for SEM analysis.
N700 Ductile Cast Iron Fast Fracture Surface

Laura Ligeski, "N700 Ductile Cast Iron Fast Fracture Surface"

The image is of a fast fracture surface of a N700 ductile cast iron sample that was loaded onto an ultrasonic fatigue machine under a constant load of 325MPa running at a pulse/pause rate of 100/1000. The fast fracture surface was caused manually when the sample was broken completely through after the test failed. The sample failed, or fractured, at 1.19x10^8 cycles due to a pore at the inside surface of the sample. This image is one of many images that will be used to help understand the properties and microstructure of this material under very high cycle fatigue.