332 research outputs found
Metagenomic analysis of microbial consortia enriched from compost: new insights into the role of Actinobacteria in lignocellulose decomposition
Additional file 11: Table S7. Summary of de novo assembly results (37Â k)
Structural Color 3D Printing By Shrinking Photonic Crystals
The rings, spots and stripes found on some butterflies, Pachyrhynchus
weevils, and many chameleons are notable examples of natural organisms
employing photonic crystals to produce colorful patterns. Despite advances in
nanotechnology, we still lack the ability to print arbitrary colors and shapes
in all three dimensions at this microscopic length scale. Commercial nanoscale
3D printers based on two-photon polymerization are incapable of patterning
photonic crystal structures with the requisite ~300 nm lattice constant to
achieve photonic stopbands/ bandgaps in the visible spectrum and generate
colors. Here, we introduce a means to produce 3D-printed photonic crystals with
a 5x reduction in lattice constants (periodicity as small as 280 nm), achieving
sub-100-nm features with a full range of colors. The reliability of this
process enables us to engineer the bandstructures of woodpile photonic crystals
that match experiments, showing that observed colors can be attributed to
either slow light modes or stopbands. With these lattice structures as 3D color
volumetric elements (voxels), we printed 3D microscopic scale objects,
including the first multi-color microscopic model of the Eiffel Tower measuring
only 39-microns tall with a color pixel size of 1.45 microns. The technology to
print 3D structures in color at the microscopic scale promises the direct
patterning and integration of spectrally selective devices, such as photonic
crystal-based color filters, onto free-form optical elements and curved
surfaces
Eight-input optical programmable logic array enabled by parallel spectrum modulation
Despite over 40 years' development of optical logic computing, the studies
have been still struggling to support more than four operands, since the high
parallelism of light has not been fully leveraged blocked by the optical
nonlinearity and redundant input modulation in existing methods. Here, we
propose a scalable multi-input optical programmable logic array (PLA) with
minimal logical input, enabled by parallel spectrum modulation. By making full
use of the wavelength resource, an eight-input PLA is experimentally
demonstrated, and there are 2^256 possible combinations of generated logic
gates. Various complex logic fuctions, such as 8-256 decoder, 4-bit comparator,
adder and multiplier are experimentally demonstrated via leveraging the PLA.
The scale of PLA can be further extended by fully using the dimensions of
wavelength and space. As an example, a nine-input PLA is implemented to realize
the two-dimensional optical cellular automaton for the first time and perform
Conway's Game of Life to simulate the evolutionary process of cells. Our work
significantly alleviates the challenge of extensibility of optical logic
devices, opening up new avenues for future large-scale, high-speed and
energy-efficient optical digital computing
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