Metal that Conducts Electricity but not Heat. Physicists at the Lawrence Berkeley National Lab and UC Berkeley have found a metal that contradicts the Wiedermann-Franz Law. This Law states that good conductors of electricity will also be proportionately good conductors of heat. The physicists were working with vanadium dioxide and unexpectedly discovered this property. There are a few other materials that are much better at conducting electricity than heat, but they only do so at temperatures a few hundred degrees below zero. It appears vanadium dioxide can do this at room temperatures. This property is derived from the fact that electrons move through the metal in a synchronized manner which is normally observed only in fluids, instead of individually which is normally observed in metals.
There is great potential for a material with this property – it could be used as an insulator in computers to keep components cool and to drastically lower the cooling costs experienced in data centers. On a more macro level this could lead to better insulation in homes and appliances and could drastically improve energy efficiency in a wide range of applications.
Superconductor Graphene. Researchers at the University of Cambridge in the UK have found a way to induce superconductivity in graphene. Today all superconducting materials only function at temperatures below -454 degrees Fahrenheit. But their research indicates superconducting graphene will work at much higher temperatures. The researchers created superconducting properties by layering graphene only on an underlying sheet of metal.
Superconduction is a big deal, because in the ultimate state a superconductor passes electrons with zero resistance. Compare that to normal materials, such as our electric grid that loses 7% of generated power getting to homes, and the difference is remarkable. Finding a room-temperature superconductor would be a huge breakthrough because it could mean electric transmissions with no power losses and an end to the heat generated in electronics and appliances that comes from resistance.
Mass Producing Graphene. Scientists at Kansas State have found a cheap way to mass produce graphene. They discovered the process when working with carbon soot aerosol gels. The process is simple and only requires hydrocarbon gas, oxygen and a spark plug. The gases are forced into a chamber and graphene is formed with a spark. This is a low-power way to make graphene since it only needs a spark rather than continuous power.
Until now graphene has been expensive to make in quantities greater than milligrams and the process required caustic chemicals. With this method it’s easy to make graphene in gram quantities and the process ought to be scalable to much larger quantities.
Better Use of Wireless Spectrum. Engineers at UCLA have found a technique that might allow better use of wireless spectrum. They have found a way to use a tiny device called a circulator that allows a chip to use both incoming and outgoing signals of a given spectrum at the same time. Today’s technology only uses spectrum in one direction since dual use of spectrum has caused interference.
Circulators have been tried before, but earlier devices used magnetic materials which can’t be incorporated into chips. The prototype they built uses coaxial cables to route the signals through non-magnetic materials and they believe the design can be built directly into silicon.
The circulator works by sequentially switching signals using different paths in a similar manner that a busy train station can have trains coming in going in both directions. The design uses six transmission lines and five switches which are turned off and on sequentially to allow incoming and outgoing signals to pass each other without interference.
This would be a big breakthrough for cellphones since it would allow for better use of the spectrum. This wouldn’t increase data speeds, but would allow a cell site to handle more phones at the same time.