IBM Demonstrates 100GHz Graphene Based Transistors


IBM has been working on graphene transistors for a while now. The new transistor prototypes are made from sheets of carbon just one atom thick that switch on and off at 100 gigahertz, this is 10 times faster than any silicon equivalents.

Electrons are able to travel through graphene much faster than other candidate materials. It is one of the likeliest materials to replace silicon in computer processing.

But researchers had previously made graphene transistors via a time consuming methods such as flaking off graphene sheets from graphite.

The labs at IBM are growing graphene transistors on a silicon carbide wafer, and then they add an insulating layer which prevents short circuits in the transistors. IBM’s  work on this was supported by DARPA.

IBM anticipate being able to scaling up the process so that they could put transistors into high performance imaging devices, radar and communication gadgets within the next few years. Graphene based computer processors might take another decade at least.

Greener Computer Chips and the Landauer limit


The future of computers could Be Magnetic, and they may consume tiny amounts of energy

The industrialised world is in love with gadgets, and even third world countries are getting the habit as they edge into the first world.

Meanwhile the combined data centres of the world are burning ever more energy and yet still more to keep them from melting down. The increasing processing power of the latest and future chips, our love for smart phones, TVs, and if nothign changes then then the must have tech toys in 20 years’ will only exacerbate this problem.

Researchers at the University of California, Berkeley have discovered that microprocessors using tiny magnets for logic, memory, and switching operations would dissipate just 18 millielectron volts of energy per operation done at room temperature. The goal is a computer that operates at the Landauer limit.

The Landauer limit is the expression for the minimum energy dissipation from a logically irreversible binary operation. The ideas behind it suggested by John von Neumann, and then developed further Rolf Landauer in 1961. Landauer stated that “any logically irreversible manipulation of information, such as the erasure of a bit or the merging of two computation paths, must be accompanied by a corresponding entropy increase in non-information bearing degrees of freedom of the information processing apparatus or its environment”.

A Berkeley news release said “Even if we could get within one order of magnitude, a factor of 10, of the Landauer limit, it would represent a huge reduction in energy consumption for electronics, it would be absolutely revolutionary.”

If Berkeley can pull this off then it would lead to advancement for in chip design.

Meanwhile over in DARPA they are chasing a new breed of portable electronics, sensors and UAVs. They are looking at logic devices that compute via magnetic moment. The magnetic moment is a quantity that determines the force a magnet can exert on electric currents and the torque that a magnetic field will exert on it. A loop of electric current, a bar magnet, an electron, a molecule, and a planet all have magnetic moments.

If DARPA get this right then they will have something that will maintain its computational state even after power is removed and by its nature is hardened against radiation.

As the man said “the times they are a changing”.