Patterning Semiconductor Building Blocks in 2D Crystals
July 22, 2015 — For the first time, researchers have synthesized lateral semiconductor heterojunctions in lithographically patterned arrays within a two-dimensional semiconductor crystal monolayer by a novel process that selectively converted exposed regions of a monolayer of MoSe2 to MoS2 using laser-deposited sulfur.
Guidelines Clarify Origins of Ferroelectric Signals
July 21, 2015 — Recent developments in piezoresponse force microscopy (PFM) and spectroscopy revealed the presence of electromechanical hysteresis loops in a variety of materials including inorganic oxides, polymers and bio systems. This behavior is often (mis)interpreted as evidence of ferroelectricity.
Easy phase transitions spur high piezoelectric responses
July 14, 2015 — Theoretical calculations, based on newly obtained experimental geometries in strained BiFeO3 thin films, predict an almost barrierless transition between co-existing phases. This facile transition provides insight into the origin of the high electromechanical responses found in coexisting phases in this Pb-free material.
HPC Industry Leaders Develop State-of-the-Art Network Communication Framework for Next Generation Programming Models
July 13, 2015 — UCX (Unified Communication – X) will provide platform abstractions supporting various communication technologies for high-performance compute and data platforms
Quantum switch is made in oxide superlattice
July 08, 2015 — Quantum mechanical resonant tunnelling that yields an extremely large ratio (~105) between the high and low resistance states has been realized in a deliberately designed complex-oxide superlattice. This unprecedented discovery through oxide-based quantum wells (QWs) is a stepping-stone to oxide electronics.
Strain Doping: A New Approach to Understanding and Controlling Advanced Materials
June 16, 2015 — Helium ions were used to control the length of a single axis in a crystal lattice, allowing for delicate manipulations of complex behavior. This accomplishment unlocks the door to engineering next-generation complex materials.
Electron Beam Guides Engineering of Functional Defects
May 20, 2015 — The electron beam of a scanning transmission electron microscope was applied to generate Se vacancies in a semiconducting monolayer of MoSe2, provide energy to drive the formation and growth of inversion domains and metallic 60˚ grain boundaries, and track the dynamics.
Oxygen Controls Surface of Epitaxial Manganite Films
May 18, 2015 — This atomically resolved study revealed a strong link between oxygen pressure and both surface-structure formation and growth dynamics in manganite thin films. The work provides key insights into controlling atomic-level behavior necessary for growing functional materials, such as manganese oxides for electronic and solid-oxide fuel cell applications.
Confining Liquids in Hollow Nanospheres Can Yield Superior Quasi-Solid Electrolytes
May 06, 2015 — The growth and proliferation of lithium dendrites during cell recharge seriously hinder development and application of rechargeable Li-metal batteries. Researchers developed a promising strategy for fabrication of quasi−solid electrolytes with superior lithium ionic conductivities, by using a hollow silica (HS) nanosphere-film architecture that blocks dendrites.
Materials scientists use ORNL’s CADES to transform big data to ‘smart data’ for rapid image analysis
April 20, 2015 — Materials scientists use ORNL’s CADES to transform big data to ‘smart data’ for rapid image analysis. ORNL material sciences researchers are collaborating with computer scientists in ORNL’s Compute and Data Environment for Science (CADES) to create a processing and analysis workflow for the expansive scanning probe and electron microscopy data generated at the Center for Nanophase Materials Sciences (CNMS).