Category Technology/Electronics

New Material Combines Useful, Typically Incompatible Properties

Geometric stabilization of polar NdNiO3 via octahedral tilt engineering.

Geometric stabilization of polar NdNiO3 via octahedral tilt engineering.

Engineers and Physicists have created an entirely new material in which completely contradictory properties can coexist.”Polar metals should not be possible,” says Chang-Beom Eom, the professor of materials science and engineering. Undeterred by the laws of the universe, Eom et al created a compound that is a scientific oxymoron. Through a new synthesis approach supported by computational modeling, the group made a crystal with multiple personalities: part polar, part metallic.

Metals conduct electricity because electrons flow freely throughout them. Polar materials, by contrast, impede the free flow of electrons and work as electrical insulators. First, they separated the polar and metallic parts of the crystal...

Read More

Team Builds 1st Quantum Cascade Laser on Silicon

3-D artistic depiction of multiple Quantum Cascade Lasers integrated above silicon waveguides. Credit: Alexander Spott

3-D artistic depiction of multiple Quantum Cascade Lasers integrated above silicon waveguides. Credit: Alexander Spott

The advance will have many uses including chemical bond spectroscopy and gas sensing, to astronomy and free-space communications. Integrating lasers directly on silicon chips is challenging, but it is much more efficient and compact than coupling external laser light to the chips. The indirect bandgap of silicon makes it difficult to build a laser out of silicon, but diode lasers can be built with III-V materials such as InP or GaAs. By directly bonding an III-V layer on top of the silicon wafer and then using the III-V layers to generate gain for the laser, this same group has integrated a multiple quantum well laser on silicon that operates at 2 µm...

Read More

Researchers develop new Semiconducting Polymer for forthcoming Flexible Electronics

While high-mobility p-type conjugated polymers have been widely reported, high-mobility n-type conjugated polymers are still rare. In the present work, we designed semifluorinated alkyl side chains and introduced them into naphthalene diimide-based polymers (PNDIF-T2 and PNDIF-TVT). We found that the strong self-organization of these side chains induced a high degree of order in the attached polymer backbones by forming a superstructure composed of “backbone crystals” and “side-chain crystals”. This phenomenon was shown to greatly enhance the ordering along the backbone direction, and the resulting polymers thus exhibited unipolar n-channel transport in field-effect transistors with remarkably high electron mobility values of up to 6.50 cm2 V–1 s–1 and with a high on–off current ratio of 105.

While high-mobility p-type conjugated polymers have been widely reported, high-mobility n-type conjugated polymers are still rare. In the present work, we designed semifluorinated alkyl side chains and introduced them into naphthalene diimide-based polymers (PNDIF-T2 and PNDIF-TVT). We found that the strong self-organization of these side chains induced a high degree of order in the attached polymer backbones by forming a superstructure composed of “backbone crystals” and “side-chain crystals”. This phenomenon was shown to greatly enhance the ordering along the backbone direction, and the resulting polymers thus exhibited unipolar n-channel transport in field-effect transistors with remarkably high electron mobility values of up to 6...

Read More

Nano-Magnets produce 3D images

This is a 3-D wireframe-cube image of nano-magnetic pixels above a real nut.

This is a 3-D wireframe-cube image of nano-magnetic pixels above a real nut.

Toyohashi Tech has developed a wide-view 3D holographic display composed of nano-magnetic pixels. This 3-D display, with 1-µm-pitch pixels, can show holographic images at viewing angle of over 30°. This display is an attractive option for visualizing 3-D objects with a smooth motion parallax and without using special glasses.

Conventional 3D displays, such as stereo displays with glasses and glass-free autostereoscopic displays, show 2D images for each eye. Therefore, users experience incongruity and eyestrain owing to these pseudo-3D images. A holographic display produces an exact copy of the wave front of scattered light from an object, and hence, a realistic 3D display is expected...

Read More