Increase core counts, decrease transistor size, increase clock speed .... thats the trend the processor manufacturing giants like Intel and AMD have been following. All of this is being done to satisfy the ever-increasing and seemingly never-ending hunger of human beings for faster, powerful and meaner computing machines. These CPU manufacturing companies have done their best to keep Gordon Moore happy .
The CPUs which are built using CMOSes , now a days are fabricated using 45 nm chip fabrication techniques, which can and will go down to 11 nm by 2015. But beyond that there is a dead end or so it seems. At these dimensions, the transistors are affected by quantum tunneling which renders them unfit for operation. And increasing clock frequency ain't going to help much either, because of inherent microelectronics limitation like low switching speeds which cause delay, and 'interconnection bottleneck' which are caused due to wiring and cause even more delay. And finally theres Mr. Heat who seemingly just cant have enough. The power dissipated in the form of heat by CPU is also growing at an alarming rate with the advent of newer and faster processors and our engineers are already having a hard time dealing with it. And all these are the limitations are posing as a wall in front of Moore's law and sadly enough they cant be avoid no matter what. Clearly one can see the night approaching and that too fast .So is there any ray of hope?
How about a song?
Take my hand,
We're off to a never never land.
Thats a Digitizor-edit version of Metallica's Enter Sandman song. And it aptly describes the future. Photonics is the solution we have been seeking. Yes, instead of electrons , light will be flowing through the veins of future generation CPUs. Imagine , the laptop you will be carrying around in not-so-distant future will actually be faster than a CRAY supercomputer.
And its not a dream at all. Giants like Intel have already spent billions in photonics research. An Israel based company named Lenslet Ltd. have already launched a DSP named EnLight which utilizes photons instead of electrons and truly is worlds first optical processor.It is claimed to be 1000 times more faster than any present day DSP.
The advantages are obvious, no delay/lags , no heat, just pure lightning speed , all of which translates to an computing experience of altogether different level where everything is not just fast but lightning fast! The switchover to optical CPUs is expected to be gradual like first stage will consist of Optical fibre cables replacing standard electrical wiring inside a CPU to tansfer information thereby removing 'interconnection bottleneck',while computation still being carried by electronic components and second stage will be removal of the remaining electronic components like those used for computational purposes. Optical processors will make resource heavy tasks like real time, multi channel video compression and processing at high image resolutions (H.264 compression for multi HDTV channels) , improving image resolution for radars, playing cinema quality games at ultra high resolutions , a breeze.
As history repeats itself , Photonics will very well do the same thing to transistors which transistors did to vacuum tubes few decades ago. Remember Matrix Revolution : Everything that has an begining must have an end.