Category Technology/Electronics

Electronically Connected Graphene Nanoribbons foresee High-Speed Electronics

Figure 1 shows interconnected graphene nanoribbons (GNRs). The interconnection points are observed as elbow structures. The inset of (a) shows the chemical structure of an elbow interconnection point of two chiral-edge GNRs. The top panel of (b) shows the scanning tunneling microscopy topograph, highlighting a single GNR and a pair of connected GNRs (elbow). The bottom panel of (b) shows the local density of states (LDOS) of these two structures share the same electronic architecture, including the elbow interconnection point. This indicates that electronic properties, such as electron and thermal conductivities, should be comparable between termini 1-2 and termini 3-4. Credit: Patrick Han

Figure 1 shows interconnected graphene nanoribbons (GNRs). The interconnection points are observed as elbow structures. The inset of (a) shows the chemical structure of an elbow interconnection point of two chiral-edge GNRs. The top panel of (b) shows the scanning tunneling microscopy topograph, highlighting a single GNR and a pair of connected GNRs (elbow). The bottom panel of (b) shows the local density of states (LDOS) of these two structures share the same electronic architecture, including the elbow interconnection point. This indicates that electronic properties, such as electron and thermal conductivities, should be comparable between termini 1-2 and termini 3-4. Credit: Patrick Han

Chemical interconnection bridges electronic properties of graphene-nanoribbons with zigzag-edge featu...

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A ‘Printing Press’ for Nanoparticles

This is a gold nanoparticle, brought into contact to a DNA nanostructure, sticks to chemical patches. Scientists then dissolve the assembly, separating the DNA nanostructure into its component strands and leaving behind the DNA imprint on the gold nanoparticle. Credit: Thomas Edwardson

This is a gold nanoparticle, brought into contact to a DNA nanostructure, sticks to chemical patches. Scientists then dissolve the assembly, separating the DNA nanostructure into its component strands and leaving behind the DNA imprint on the gold nanoparticle. Credit: Thomas Edwardson

New technique could facilitate use of gold nanoparticles in electronic, medical applications. Gold nanoparticles have unusual optical, electronic and chemical properties, which scientists are seeking to put to use in a range of new technologies, from nanoelectronics to cancer treatments.

Some of the most interesting properties of nanoparticles emerge when they are brought close together – either in clusters of just a few particles or in crystals made up of millions of them...

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Single-Chip Laser Delivers Powerful Result

A schematic of the new laser system. Credit: Image courtesy of Northwestern University

A schematic of the new laser system. Credit: Image courtesy of Northwestern University

High power and rapid tuning for the detection of hazardous chemicals. From their use in telecommunication to detecting hazardous chemicals, lasers play a major role in our everyday lives. They keep us connected, keep us safe, and allow us to explore the dark corners of the universe. Now a Northwestern University team has made this ever-important tool even simpler and more versatile by integrating a mid-infrared tunable laser with an on-chip amplifier. This breakthrough allows adjustable wavelength output, modulators, and amplifiers to be held inside a single package.

With this architecture, the laser has demonstrated an order-of-magnitude more output power than its predecessors, and the tuning range has ...

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New Efficiency Record Set with Dual-Junction Solar Cell

GaInP/SHJ tandem solar PV cells with efficiency up to 29.8% under 1-sun standard illumination

GaInP/SHJ tandem solar PV cells with efficiency up to 29.8% under 1-sun standard illumination

NREL and CSEM scientists have jointly set a new world record for converting non-concentrated (1-sun) sunlight into electricity using a dual-junction III-V/Si solar cell. The newly conversion efficiency of 29.8% was set using a top cell made of gallium indium phosphide developed by NREL, and a bottom cell made of crystalline silicon developed by CSEM using silicon heterojunction technology. The two cells were made separately and then stacked by NREL.

“It’s a record within this mechanically stacked category,” said David Young, a senior researcher at NREL. “The performance of the dual-junction device exceeded the theoretical limit of 29.4% for crystalline silicon solar cells.”
“We believe that the si...

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