Technologies That Will Revolutionize Computing

It’s hard to imagine life before the computer revolution.  Dictionaries and thesauruses were necessities and a spell-checker was a generous colleague.  Research projects required trips to libraries, card-catalogues, and an understanding of the Dewey Decimal system.  In a matter of years we’ve transitioned to complete reliance on computers.

My own upbringing straddled this transition.  Sometime in elementary school, classrooms began to be equipped with a handful of computers, but they weren’t good for much more than loading Oregon Trail off of 3 1/2 inch floppies.  Then there was an awkward iMac phase in middle school, where the computer, for me, began to take over as the primary word processor and websites like hamsterdance.com began annoying everyone.  By high school, the internet was in full swing, and illegal file sharing was all the craze.

Computers have grown with us, and they’re continually changing and improving.  Gordon Moore claimed in the 1960s that the number of transistors on the microchip will double every two years, and his prediction was surprisingly accurate.  Here are three technologies that may take computers to the next generation.

Graphene - Understanding graphene means understanding carbon.  Elemental carbon (substances made of only pure carbon) exists in only a few forms here on earth.  Amorphous carbon, coal or soot, is just a jumble of carbon atoms with no organized lattice.  Diamonds on the other hand, have their carbon atoms formed in a precise 3D lattice. 

This lattice is what makes diamonds the hardest substance known.  Then there is graphite, whose lubricative properties couldn’t be more different from diamonds.  Graphite is made of layers of 2D carbon lattices, sheets of carbon arranged in six membered rings, stacked on top of each other.  These sheets are only weakly held to one another, and can easily slide apart, making graphite the lubricant we know and love.

If you isolate just one of these carbon sheets, you’ve got one of the new wonder materials.  Graphene, only first isolated in 2004, is the basis for carbon nanotubes – graphene sheets rolled into tubes.  But Graphene is known for more than just nanotubes.  It’s the strongest material in the world, and more importantly, it’s also the best conductor in the world (at room temperature).  Using graphene in computers could reduce the power lost in the circuit board and lower demands on the cooling system.

Graphene owes its fantastic properties to its molecular structure.  The carbon atoms in graphene are arranged in a flat sheet comprised of six memebered rings.  This sheet, essentially a benzene quilt, is a particularly stable form of carbon whose covalent bonds easily share electrons, making it sturdy and conducting.  Being a single atom thick, however, makes graphene difficult to produce in large quantities (its worth more per gram than gold).  Oddly enough, all you need to isolate graphene (on the micrometer scale) is a graphite pencil, scotch tape, an optical microscope, and loads of free time.

Optical Microchips – One of the determining factors of computer performance, if we listen to Mr. Moore, is the amount of transistors on the processor.  Processor manufacturers like Intel currently use optical lithography techniques to put millions of transistors in their processors.  But as these techniques rely on light waves, there is an overall limit to how small they can go – the diffraction limit.  While companies like Intel keep their lithography techniques well guarded (and it is an impressive feet to make a million transistors with NO errors), the diffraction limit will one day stop progress dead in its tracks.

But, there are alternatives to traditional semi-conductor transistors.  Current research in plasmonics has demonstrated one such possible alternative.  The plasmon transistor, or “plasmonster,” uses strange quantized electron density waves that occur on the surface of certain metals.  The waves, or plasmons, are excited by laser signals, and share many of the characteristics of normal transistors with electric signals.  Other techniques have used single molecules only 2 nanometers in size to produce an optical transistor.

Wireless Power Transfer – In the last several years, we’ve began to see the messy tangle of chords behind the computer desk untangle.  Wireless internet routers have detethered our computers from the Ethernet cords, and some even allow wireless networking to peripherals.  But every computer is still chained down - at least part of the time - by a thirst for electricity.

Wireless power transfer is not a new phenomenon.  Nikola Tesla was lighting bulbs wirelessly before the turn of the twentieth century, so why haven’t we found a way to charge our portable electronics without cords?  Well, efficiently and safely transmitting power is a little more complicated than Tesla’s demonstrations.

There are many ways to transmit power wirelessly.  Electromagnetic radiation could do the trick; however, transmitting energy in every direction would lose a vast majority of the power (volume is proportional to r3). Directed EM radiation like a laser could work better, but this could be quite dangerous, not to mention the need for an uninterrupted line of site, rendering you as immobile as with a power cord.

The best way to transfer energy wirelessly is through induction.  Michael Faraday discovered that a time changing magnetic field will induce an electric current in a conductor.  So theoretically all we need for wireless power is a magnetic field generator and a conductor.  It turns out, while this is better than radiation, the efficiency is still not good over reasonable distances.

A more efficient way of inducing current would be to have a receiver that resonates with the frequency being produced (coupled to the generator).  Resonance is a powerful physical phenomenon.  It’s responsible for wine glasses shattering when an opera singer hits just the right note, or for the dramatic destruction of the Tacoma Narrows Bridge.  If the receiver behaved in resonance with the generator, much more efficient power transfers can be achieved.  And since magnetic fields pose little risk to living things, it would be safe as a well.

Well, we’ve been using inductive coupling to power pacemakers wirelessly for many decades now.  Transformers are also full of inductively coupled coils.  The problem is that these operations only require power over small distances; energy transfer is still inefficient over large distances.  But we’re getting closer.  In 2007, a group at MIT successfully transferred 60 watts of electricity wirelessly over two meters with 40% efficiency.

Computers are evolving at a rapid pace these days, taking on new forms and integrating into other electronics.  Mobile phones are now half-computers and ultra-portable netbooks are gaining in popularity, allowing for computers to creep in to more aspects of our lives.  But no matter how far we come, I’ll always have fond memories of hunting more buffalo than our wagon can carry (on Oregon Trail).

Questions and comments: andrewhaynie2009@u.northwestern.edu