It’s a hot summer day. You desperately want something cold to drink, but unfortunately, your bottle of root beer has been sitting in a hot car all day. You put it into a bucket full of ice to cool it down. But it’s taking forever! How, you wonder, could you speed the process up? The same question is important for understanding how electronic devices work, and how we can make them work better by controlling the temperature of the electrons that power them. Read on to find out what a bottle of root beer in a cooler full of ice and a nanowire in a vat of liquid helium have in common!
Diodes, also known as rectifiers, are a basic component of modern electronics. As we work to create smaller, more powerful and more energy-efficient electronic devices, reducing the size of diodes is a major objective. Recently, a research team from the University of Georgia developed the world's smallest diode using a single DNA molecule. This diode is so small that it cannot be seen by conventional microscopes.
You’re lining up your phone to take a picture of your dog. Light comes down from the sun, bounces off the dog, and into your camera lens, allowing you to take the photo. Your eyes work similarly, taking in all the light particles, known as photons, that are scattering off of objects in the world. Most things “see” by detecting these bouncing photons, which is why both you and your phone have a hard time seeing anything at all when the lights are off.
Think of the hard disk in your computer. Information is stored there in the form of magnetic "bits." But do you know how small a magnet can be? Some molecules make magnetic magic, and these special molecules may give rise to the ultrafast, high precision, low power devices of the future.
How can you fabricate a huge number of nanostructures in a split second? Self-assembly is a fast technique for the mass production of materials and complex structures. But before self-assembly is ready for prime time, scientists need to establish ways to control this process, so that desired nanostructures emerge from the unstructured soup of basic building blocks that are fast-moving atoms and molecules.
Very small structures, much smaller than the human eye can see, often fall in the size range of nanometers. By understanding how the molecules that make up these structures interact, we can engineer them to do many special things that cannot be done at a larger scale. One exciting structure is a polymer brush, in which long, chain-like molecules called polymers are tethered at one end to a surface and stick up from the surface like bristles on a hairbrush. Polymer brushes can be used to keep bacteria away, provide an exceptionally smooth surface for items to slide across, or trap other molecules in solution like a hairbrush traps loose hair. In order to engineer polymer brushes that will perform as desired for a given application, we must understand the physics of how the molecular bristles move, and the chemistry of how they interact with their environment.
AtomTouch is a free, interactive molecular simulation app, created by researchers at the University of Wisconsin Materials Research Science and Engineering Center (UW MRSEC) to allow learners to explore principles of thermodynamics and molecular dynamics in an tactile, engaging way.