#sutd

Pressure turns Ångström-thin semiconducting bismuth into a metal, expanding options for reconfigurable electronics

Two-dimensional (2D) materials, sparked by the isolation of Nobel-prize-winning graphene in 2004, has revolutionized modern materials science by showing that electrical, optical, and mechanical behaviors can be tuned simply by adjusting the thickness, strain, or stacking order of such 2D materials. From transistors and flexible display to neuromorphic chips, the future of electronics is expected to be significantly empowered by 2D materials. In a new study published in Nano Letters titled "Pressure-Driven Metallicity in Ångström-Thickness 2D Bismuth and Layer-Selective Ohmic Contact to MoS2," researchers led by SUTD have discovered that a gentle squeeze is enough to make bismuth—one of the heaviest elements in the periodic table—switch its electrical personality. Using state-of-the-art density functional theory (DFT) simulations, the team showed that when a single layer of bismuth, only a few atoms thick, is compressed or "squeezed" between surrounding materials, the atoms reorganize from a slightly corrugated (or buckled) structure into a perfectly flat one. This structural flattening, though subtle, has dramatic electronic consequences: it eliminates the energy band gap and allows electrons to move freely, turning the material metallic.

#designoftheday - 20 September 2018:  The Future of Us Exhibition Pavilion by SUTD Advanced Architecture Laboratory. . The Singapore University of Technology and Design (SUTD) Advanced Architecture Laboratory (AAL) was commissioned to design this large-scale exhibition pavilion for The Future of Us exhibition, the capstone event to round up Singapore’s Golden Jubilee (SG50) year of celebrations, in late 2014. The visitors of the exhibition experience a stunning play of light and shade cast by an intricate metal lattice, like a ‘walk in an imaginary forest’. .

Glass nanostructures reflect nearly all visible light, challenging photonics assumptions

A research team led by SUTD has created nanoscale glass structures with near-perfect reflectance, overturning long-held assumptions about what low-index materials can do in photonics. For decades, glass has been a reliable workhorse of optical systems, valued for its transparency and stability. But when it comes to manipulating light at the nanoscale, especially for high-performance optical devices, glass has traditionally taken a backseat to higher refractive index materials. Now, a research team led by Professor Joel Yang from the Singapore University of Technology and Design (SUTD) is reshaping this narrative. With findings published in Science Advances, the team has developed a new method to 3D-print glass structures with nanoscale precision and achieve nearly 100% reflectance in the visible spectrum. This level of performance is rare for low-refractive-index materials like silica, and it opens up a broader role for glass in nanophotonics, including in wearable optics, integrated displays, and sensors.