The New Frontier of Physics Is Where A Few Atoms Are Made to Come Together
Biplab Bhawal [photo by Chris Walter]
At the end of the summer of 2010, my 17-year old son landed in Carnegie Mellon University armed with a laptop, an iPhone and a Kindle to start his freshman year. All of these three devices had lots of scratches on them, and they looked as dirty as they should be for being dedicated slaves (no fix hour, no health benefit) of an owner who had just recently found some sort of liberty and so cared less for anything sub-human (e.g., that laptop) or human (e.g., me).
The Laptop had 500GB memory, the iPhone had 32GB, and the Kindle could potentially hold 3500 books. Their owner knew those numbers by heart. If you had asked him -- he would have uttered those with such carelessness (rude!) as if the ability to speak of these numbers was just another birthright he naturally deserved.
When he threw his laptop on his dorm bed with scant respect for this slave of his, I looked at that incorrigible offspring of mine in disgust -- sharing the feeling of those million Dads who were not on the right side of 40. I tried hard to remember what visual as well as functional meaning the word ‘computer’ had during my high school or college years.
In the year 1980, I was too young to take any particular notice of two events that had happened in preparation for a larger revolution : (i) Seagate Technology introduced the first 5.25 inch hard disk drive, ST-506, which could store up to 5MB after formatting, and (ii) IBM introduced the world's first GB-capacity disk drive, the IBM 3380 which had the size of a refrigerator, weighed 550 pounds, and had a price tag of $40,000 (After 30 long years … those three gadgets my son now has, had cost him about 1/30th of that – a part of his low-wage earning from a summer job. For a change, I do not have any complaint against such a purchase).
In 1988, while training myself hard to become a physicist, I was not ready yet to notice the discovery of an important physical effect: 'Giant Magnetoresistance’ or GMR – independently by a French physicist named Albert Fert and a German physicist named Peter Grünberg. They observed that very weak magnetic changes give rise to major differences in electrical resistance in a GMR system. Once the effect was discovered, it was easy for researchers and engineers to envision that GMR could be a perfect tool for reading data from hard disks.
GMR can be considered one of the first real applications of nanotechnology. The effect was discovered thanks to new techniques developed during the 1970s to produce very thin layers of different materials. If GMR is to work, then structures consisting of layers that are only a few atoms thick have to be produced.
The first read-out head based on the GMR effect was launched in 1997. This soon became the standard in the industry and revolutionized the way for miniaturizing hard disks ever since. For deserving reasons, Fert and Grünberg were awarded the Physics Nobel prize in 2007.
At the end of the last millennium, to many physicist friends of mine, the phrase ‘Frontier of Physics’ had meant only two (but still interrelated) ends of the whole spectrum of physics research activities: elementary particles and the universe. All else in between were just parts of the details that the creator of the universe left for the demon.
However, the first decade of the new millennium has seen some crucial developments in our understanding of how atoms and molecules interact with each other. This might force those physicists to change their views about ‘the details’. Discoveries of new unheard-of phenomena in nanoscale realms of matter have enriched physics in a truly spectacular way. For example, electromagnetic metamaterials or artificially engineered (usually in structure rather than in composition) materials provided new grounds for the discovery of unusual physical properties not available in nature: negative refraction index, superlenses with resolution below wavelength, invisibility cloaks, optical magnetism, asymmetric transmission – to name only a few. This, along with the application of effects like Surface Plasmon Resonance (SPR), is leading the way for the development of future devices. People developing new kind of semiconductor nanocrystals like quantum dots started talking about the effects of quantum confinement of electrons and holes. Quantum entanglement of ensembles of atoms became a hot field of research. Newly discovered effects and newly developed devices started to enrich the field of quantum computation and communication.
Thin crystalline material like Graphene with thickness of only one or several atoms is now providing physicists new opportunities for experiments that may give new twists to the phenomena in quantum physics. It’s presenting a new class of two-dimensional materials with unique properties. These have a vast variety of practical applications like the manufacture of innovative electronics including Graphene transistors which would be substantially faster than today’s silicon transistors leading to more efficient computers.
The atomic scale had ceased to generate any sustained level of enthusiasm quite some time back. Now, the nanoscale has assumed the role of the new frontier where mankind is trying to play the role of the Creator by bringing in a few atoms or molecules together and discovering some hitherto unheard-of physical effects. The dream that Feynman saw 51 years back is now taking shape in laboratories throughout the world: “I want to build a billion tiny factories, models of each other, which are manufacturing simultaneously. . . The principles of physics, as far as I can see, do not speak against the possibility of maneuvering things atom by atom. It is not an attempt to violate any laws; it is something, in principle, that can be done; but in practice, it has not been done because we are too big.” [From There's Plenty of Room at the Bottom, a lecture given by Richard Feynman at the American Physical Society meeting held at Caltech on December 29, 1959].
In the new decade we can hope to see much more progress in this new realm of physics. Newer devices are on their way, which will exploit the complex quantum interaction of matter and utilize recently discovered physical phenomena.
Throughout the development of the electronics and computer industry, engineering graduates could afford to live their career with only a little almost-qualitative description of quantum mechanics in their curriculum. In this new decade, we should certainly see one or more involved courses of quantum mechanics becoming an essential part of the engineering curriculum of any prestigious university.
We can dream that these new efforts and discoveries would finally bring to our hands and laps new gadgets and toys -- as handsome, as convenient, as presentable and as useful as a laptop is.
Hopefully, we will find time to sit quietly alone with our laptops and such gadgets, and while looking at a specification like ‘500 GB’, we will renew the joy of realization of the theme of that great movie The Curious Case of Benjamin Button, “Life can only be understood backward”, or in the spirit of Steve Jobs’ 2005 convocation address at Stanford, “You can't connect the dots looking forward; you can only connect them looking backwards”.
But, before all those things happen, would someone please teach my son and creatures like him the need for handling those wonderful devices with the respect that they and their history and their creators deserve?