Science Critical Digest: 6.12.11

1. Quantum locking in superconductors leads to levitation! See the work done by the Superconductivity Group at Tel Aviv University here: http://www.quantumlevitation.com/levitation/See_it_in_Action.html . The website also contains a brief writeup about the physics involved.

A group at the University of Paris-Diderot has gone one better, and built a functional hoverboard, the likes of which you would have seen in the ‘Back to the Future’ films. You can see the team demonstrate their invention here: http://www.youtube.com/watch?feature=player_embedded&v=_F-VVmMD4_k

A substance is said to be a superconductor if it exhibits zero electrical resistance and ejects magnetic field lines from its interior. Unfortunately, the systems mentioned above, and indeed all superconducting systems studied thus far, require constant cooling with liquid nitrogen in order to maintain their superconductivity. As soon as they warm up, superconductivity (which is what enables levitation) is lost, thus making them functional for very short times at room temperatures. The hunt for a substance that demonstrates superconductivity at room temperature is still on.

2. A group at the University of Texas at Dallas has created a sheet of carbon nanotubes that utilises the mirage effect to work as an invisibility cloak. You can read the paper published in the journal Nanotechnology here: http://iopscience.iop.org/0957-4484/22/43/435704 and see the cloak in action: http://www.youtube.com/watch?feature=player_embedded&v=3YO4TTpYg7g

3. Scientists have used the fluorescent protein GFP from jellyfish to create living cells that can function as lasers without losing their viability. In addition to being an incredibly cool piece of science, this work has the potential to revolutionise tissue imaging and the optically-controlled release of drugs. Current limitations in the optical imaging of biological tissue is the fact that most such systems are opaque to light beyond a few layers of cells. However, if the cells themselves were sources of laser light, then the signal from biological tissue would be greatly boosted, allowing for easier imaging. Read all about it here: http://www.nature.com/nphoton/journal/v5/n7/full/nphoton.2011.99.html