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Researchers at Columbia University have discovered a new way to control the phase of light using 2D materials without changing its amplitude, at extremely low electrical power dissipation. The researchers demonstrated that by simply placing the thin material on top of passive silicon waveguides, they could change the phase of light as strongly as existing silicon phase modulators, but with much lower optical loss and power consumption.
Researchers at Columbia University have discovered a new way to control the phase of light using 2D materials without changing its amplitude, at extremely low electrical power dissipation. The researchers demonstrated that by simply placing the thin material on top of passive silicon waveguides, they could change the phase of light as strongly as existing silicon phase modulators, but with much lower optical loss and power consumption.
Researchers at Pacific Northwest National Laboratory have discovered that atomic forces thought to be "weak" can actually exert more control than has been understood. The researchers explored the formation of zinc oxide through a process in which individual nanoparticles act as building blocks that attach to each other to form a larger crystal. This discovery could help better predict and eventually control manufacturing of semiconductor materials used in electronics and other industrial applications.
Researchers at Pacific Northwest National Laboratory have discovered that atomic forces thought to be "weak" can actually exert more control than has been understood. The researchers explored the formation of zinc oxide through a process in which individual nanoparticles act as building blocks that attach to each other to form a larger crystal. This discovery could help better predict and eventually control manufacturing of semiconductor materials used in electronics and other industrial applications.
Van der Waals crystals hold great promise for electronic, optoelectronic, and quantum devices, but manufacturing them has been limited by the lack of high-throughput techniques for exfoliating single-crystal monolayers with sufficient size and high quality. Researchers at Columbia University have invented a new method using gold films to disassemble single van der Waals crystals layer by layer into monolayers with near-unity yield and with dimensions limited only by bulk crystal sizes.
Van der Waals crystals hold great promise for electronic, optoelectronic, and quantum devices, but manufacturing them has been limited by the lack of high-throughput techniques for exfoliating single-crystal monolayers with sufficient size and high quality. Researchers at Columbia University have invented a new method using gold films to disassemble single van der Waals crystals layer by layer into monolayers with near-unity yield and with dimensions limited only by bulk crystal sizes.
Metals get stronger as the size of the grains making up the metal gets smaller – up to a point. If the grains are smaller than 10 nanometers in diameter, the materials are weaker because, it was thought, they slide past each other like sand sliding down a dune. But researchers at Princeton University, the University of California, Berkeley, and at universities in China have shown that in samples of nickel with grain diameters as small as 3 nanometers, and under high pressures, the strength of the samples continued to increase with smaller grain sizes.
Metals get stronger as the size of the grains making up the metal gets smaller – up to a point. If the grains are smaller than 10 nanometers in diameter, the materials are weaker because, it was thought, they slide past each other like sand sliding down a dune. But researchers at Princeton University, the University of California, Berkeley, and at universities in China have shown that in samples of nickel with grain diameters as small as 3 nanometers, and under high pressures, the strength of the samples continued to increase with smaller grain sizes.
Engineers at MIT have developed a small, mirrored chip that helps to produce dark-field images without dedicated expensive components. When placed on a microscope's stage, the chip emits a hollow cone of light that can be used to generate detailed dark-field images of algae, bacteria, and similarly translucent tiny objects. The middle layer of the optical chip functions as the chip's light source, made from a polymer infused with quantum dots—tiny nanoparticles that emit light when excited with fluorescent light. Over this light-generating layer, the researchers placed a structure made from alternating nanoscale layers of transparent materials, with different refractive indices.
Engineers at MIT have developed a small, mirrored chip that helps to produce dark-field images without dedicated expensive components. When placed on a microscope's stage, the chip emits a hollow cone of light that can be used to generate detailed dark-field images of algae, bacteria, and similarly translucent tiny objects. The middle layer of the optical chip functions as the chip's light source, made from a polymer infused with quantum dots—tiny nanoparticles that emit light when excited with fluorescent light. Over this light-generating layer, the researchers placed a structure made from alternating nanoscale layers of transparent materials, with different refractive indices.
