Slashdot Mirror
Optical Microchip Breakthrough In Canada?
_J_ writes: "The Toronto Star has This Article on their Web site about method to "trap light." Since they call it a break-through to making an optical system it implies that light can be stored in a type of memory. I hope that this implies light-using logical gates." While this sounds like one more Holy Grail Found! announcement, the work that professors Ozin and John (mentioned in article) have done makes it sound like they're no slouches in the photonics or nanotech departments.
So the Star's article is completely devoid of details - it's a newspaper ! I'll add a few more details so people can get as much information about this topic as they want. First and foremost the latest issue of Nature has an article entitled "Photonics: Opal appeal" specifically about this breakthrough (subscription required). The catch phrase used is a "three-dimensional photonic bandgap material". The team that's accomplished this is a bit more international then indicated so far, consisting of a Spanish team making the opal template, Geoff Ozin's group filling the lattices & then dissolving the template, Henry VanDriel's group performing the laser experiments, and Sajeev John's group providing the theory framework.
For those of you who just want pretty pictures, here are some images of the opals.
Here's the ultimate resource for photonic bandgap materials.
So that should give you more then enough to visit & read. Basically what these materials do is prevent propagation of light of a specific frequency in 3-dimensions. The 'bandgap' of the light can be controlled during the fabrication process allowing these things to block different frequencies. So you could imagine placing one of these materials into an optical fibre & selectively blocking one of the data streams but allowing all others to pass through unimpeded. The current breakthrough is twofold, first these aren't imaginary, they've been made & tested and they aren't decades removed from insertion into optical networks, they're months or years from it, second, this is the first example of a 3D PBG material, previous versions have generally been 2D. One of the neater experiments performed involved putting liquid crystals into the opal holes & then by putting an electric field across the liquid crystals, controlling the transmission through the crystal. A variable transmission photonic bandgap device. Light is fast, electrons are slow, an all optical network would be blazingly fast & these devices bring us a step closer to making that happen.
CJM
Material research has a strong component of wishful thinking and future projections. So many things don't work out because of a few insurmountable details. You need strong sources of motivation to pursue the dire road to success.
In their reasoning and justification of their work, these guys live at least 10 years into the future all the time. The referenced article was probably written by someone who took all their statements at face value. It looks to me as if they still have a long way to go. That's not meant to diminish their merits - these scientist are certainly top notch researchers and their results are truly very impressive. I just don't think they have delivered an imminent disruptive technology.
It's commonly accepted that the existence of a laboratory setup does not guarantee the technological and economical viability of any particular solution in the real world. I would start preparing for an imminent disruptive technology if a successful prototype system did exist. Yet, I don't have the feeling that there are even useful laboratory setups of the presented kinds of photonic devices. It rather looks like promising basic research.
As for the all photonics claim, I think the notion should be scaled down a little to be less prone to misunderstanding. To many people, it sounds like all photons, no electrons. I don't believe there is such a thing within our technological reach. Photons are bosons and interact extremelyweakly. That's not a very good basis for a computing device. Fortunately, photons can be converted into excited states of electrons which are fermions, interact in many ways, and can be used to produce logic gates.
That leaves us with a possible extension of the present use of photonic devices from lines of communication between nodes on a network to nano-lines of communication between old-fashioned electronic gates. And that's certainly not going to happen very soon. So, sorry my friends, no reason to get all excited.
Oooh, I'm impressed. Slashdot already has links to the homepages of the two main subjects of the story of interest. Within which details of what is likely being talked of in the Toronto Star article can be found. I wish I had noticed that before I did all that searching.
Anyways, you'll notice that the publications start back in the early 90's. The 'new' thing they've discovered together might be what is talked about here, and is more clearly described here and here (Sajeev John's page contained links to this stuff...).
It's just a new way of making something that's been researched for the past 10 years, photonic band gap materials.
I haven't seen anything yet to tell us if this is such a better way of making this class of material that it counts as a 'revolution'. We have to find someone who knows a lot more about the current state of the art in creating photonic band gap materials and get this person to analyze this new method and it's results, to tell us if it's a significant advance, or what it's advantages are.
AKA: More peer review please.
Also, since photons do not posses charge, they can not be interfered with by any kind of static electricity, magnetic fields, etc. Their signal stays truer.
Hopefully I didn't put any [] around my words.