As electronic, thermoelectric and computer technologies have been miniaturized to nanometer scale, engineers have faced a challenge studying fundamental properties of the materials involved; in many cases, targets are too small to be observed with optical instruments. Using cutting-edge electron microscopes and novel techniques, a team of researchers at the University of California, Irvine, the Massachusetts Institute of Technology and other institutions has found a way to map phonons – vibrations in crystal lattices – in atomic resolution, enabling deeper understanding of the way heat travels through quantum dots, engineered nanostructures in electronic components.
UCI scientists measure local vibrational modes at individual crystalline faults
Irvine, Calif., Jan. 11, 2021 – Often admired for their flawless appearance to the naked eye, crystals can have defects at the nanometer scale, and these imperfections may affect the thermal and heat transport properties of crystalline materials used in a variety of high-technology devices. Employing newly developed electron microscopy techniques, researchers at the University of California, Irvine and other institutions have, for the first time, measured the spectra of phonons – quantum mechanical vibrations in a lattice – at individual crystalline faults, and they discovered the propagation of phonons near the flaws.
NSF grants $18 million to UCI for materials science and engineering center
Irvine, Calif., July 14, 2020 – The National Science Foundation has awarded $18 million to the University of California, Irvine in support of a new materials research science and engineering center. UCI is one of three MRSECs newly funded by the NSF in 2020, joining 16 other existing centers at leading research institutions in the United States.
UCI-led team designs carbon nanostructure stronger than diamonds
Irvine, Calif., April 13, 2020 – Researchers at the University of California, Irvine and other institutions have architecturally designed plate-nanolattices – nanometer-sized carbon structures – that are stronger than diamonds as a ratio of strength to density. In a recent study in Nature Communications, the scientists report success in conceptualizing and fabricating the material, which consists of closely connected, closed-cell plates instead of the cylindrical trusses common in such structures over the past few decades.