Category Physics

Electrostatically Driven Nanoballoon Actuator, Nano Letters (2016). http://pubs.acs.org/doi/abs/10.1021/acs.nanolett.6b02394

Molecular sized machines could in the future be used to control important mechanisms in the body. In a recent study, researchers at University of California, Berkeley and Umeå University show how a nanoballoon comprising a single carbon molecule can be controlled electrostatically to switch between an inflated and a collapsed state. Inflatable balloon actuators are commonly used for macroscopic applications to lift buildings, as impact protection in cars or to widen narrowed or obstructed arteries or veins. At the micro scale they are used as micro pumps and in nature jumping spiders create microformat fluid-filled cushions to power their legs in explosive jumps.

I...

Los Alamos Center for Advanced Solar Photophysics researchers hold a large prototype solar window. From left to right: Jaehoon Lim, Kaifeng Wu, Victor Klimov, Hongbo Li. Credit: Los Alamos National Laboratory

Los Alamos National Lab team demonstrates an important step in taking quantum dot, solar-powered windows from the laboratory to the construction site by proving that the technology can be scaled up from palm-sized demonstration models to windows large enough to put in and power a building. “We are developing solar concentrators that will harvest sunlight from building windows and turn it into electricity, using quantum-dot based luminescent solar concentrators (LSCs),” said lead scientist Victor Klimov.

LSCs are light-management devices that can serve as large-area sunlight collectors...

Optically-driven mechanical oscillator fabricated using a plasmomechanical metamaterial.

A device fabricated using a plasmomechanical metamaterial, operates through a unique mechanism that couples its optical and mechanical resonances, enabling it to oscillate indefinitely using energy absorbed from light. This work demonstrates a metamaterial-based approach to develop an optically-driven mechanical oscillator. The device can potentially be used as a new frequency reference to accurately keep time in GPS, computers, wristwatches and other devices. Other potential applications include high precision sensors and quantum transducers.

Researchers engineered the metamaterial-based device by integrating tiny light absorbing nanoantennas onto nanomechanical oscillators...

The schematic depicts the time-resolved photoemission electron microscopy instrumentation that allowed the Femtosecond Spectroscopy Unit to visualize electron movements. The 800nm pump pulse (red) excites electrons while the weaker 266nm probing pulse (blue) allows for different measurements of electron movements to be taken. Credit: Michael Man

Ever since J.J. Thompson’s 1897 discovery of the electron, scientists have attempted to describe the subatomic particle’s motion using a variety of different means. New research from the Femtosecond Spectroscopy Unit at the Okinawa Institute of Science and Technology Graduate University (OIST) has made this process much easier.

I wanted to see the electrons move, not just to explain their motion by measuring a change of light transmission and refle...