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Sight of Superlative Achievement Submitted by Stephen Boydstun on Thu, 2007-07-05 17:35
My favorite character in Atlas Shrugged is John Galt. One of the crucial traits of this character is his extraordinary technical ability. I can adore a fictional character, and part of the reason I adore this one is his possession of that trait. Adoration is one thing, admiration is another. Galt’s technical genius is admirable only in the derivative sense that I would admire that trait in a real person. I cannot admire a fictional character. I can admire the character’s creator as creator, but not the character. Fortunately, there are in our time many individuals whose mathematical and scientific accomplishments are at the high level of the fictional character John Galt. They are not well known to the general public. I want to tell you about one such man. Eli Yablonovitch invented the concept of a photonic band gap. He arrived at this concept in 1987 while doing research on making telecommunication lasers more efficient. Another physicist Sajeev John arrived at the concept independently that same year. John came to the concept in the course of pure research attempting to create light localization. Four years later, Yablonovitch was the first to create a successful photonic band-gap crystal. He used a variant of the crystal structure of diamond, a variant now called yablonovite. The structure was formed by drilling three intersecting arrays of holes, 400 nanometers in diameter, into a block of ceramic material. This structure, at this scale, was able to eliminate the propagation of electromagnetic radiation in the microwave range. Photonic band-gap crystals are yielding a new generation of optical fibers capable of carrying much more information, and they are contributing to the realization of nanoscopic lasers and photonic integrated circuits. The name photonic crystal sounds like a crystal made of light. That is incorrect. A photonic crystal is an artificial crystal (or quasicrystal) made usually of solids such as dielectrics or semiconductors. The electrical properties of a semiconductor are intermediate between a dielectric (an insulator) and a conductor. In a dielectric material, the valence electrons of the atoms are tightly bound to them. They are confined to energy levels within the band of levels called the valence band. Above that band of levels is a broad band of energies inaccessible to the electrons under the laws of quantum mechanics. That forbidden band is called the band gap. Above the band gap is a band in which electrons could move freely in the material if only enough energy were applied to them to raise them to that band of energy levels. This band is called the conduction band. In a semiconductor, the valence electrons are less tightly bound to atoms than they are in a dielectric. The band gap is smaller. A smaller boost of energy is needed to induce the flow of electrons, a current. The degree of electrical conductivity of a semiconductor can be precisely controlled by doping one semiconductor chemical element with small amounts of another. When an electron is promoted across the band gap, an effective positive charge called a hole is created in the valence levels below the gap. The holes, like the electrons, can be entrained into currents. By controlling the supply of electrons and holes above and below the band gap, carefully designed semiconductors are able to perform electronic switching, modulating, and logic functions. They can also be contrived to serve as media for photo detectors, solid-state lasers, light-emitting diodes, thermistors, and solar cells. The properties of an electronic band gap depend on the type of atoms and their crystal structure in the solid semiconductor. To comprehend and manipulate the electronic properties of matter, electrons and their alterations must be treated not only in their character as particles, but in their character as quantum-mechanical waves. The interatomic spacing of the atoms in matter is right for wave-interference effects among electrons. This circumstance yields the electronic band gaps in semiconductors as well as the conductive ability of conductors. A photonic band gap is a range of energies of electromagnetic waves for which their propagation through the crystal is forbidden in every direction. The interatomic spacing in semiconductors are on the order of a few tenths of a nanometer, and that is too small for effecting photonic band gaps in the visible, infrared, microwave, or radio ranges of the spectrum. Creation of photonic band gaps for these very useful wavelengths requires spatial organizations in matter at scales on the order of a few hundred nanometers and above. In the 70’s and 80’s, researchers had been forming, in semiconductors, structures called superlattices. These were periodic variations in semiconductor composition in which repetitions were at scales a few times larger than the repetitions in the atomic lattice. The variations could consist of alternating layers of two types of semiconductors or in cyclic variations in the amount of selected impurities in a single type of semiconductor. These artificial lattices allowed designers, guided by the quantum theory of solids, to create new types of electronic band gaps and new opticoelectronic properties in semiconductors. Photonic crystals are superlattices in which the repeating variation is a variation in the refractive index of the medium. It is by refractions and internal partial reflections that photonic band gaps are created. The array of holes that Yablonovitch and his associates drilled for the first photonic crystal formed a superlattice of air in the surrounding dielectric solid. Additional workable forms of photonic-crystal superlattice have been demonstrated since that first one. Costas Soukoulis and colleagues created a crystal of crisscrossed rods, and it has yielded photonic band gaps in the infrared part of the spectrum. Photonic crystals have been created mostly in dielectric or semiconductor media, but Shawn Yu Lin and associates have created them in tungsten. These may prove useful in telecommunications and in the conversion of infrared radiation into electricity. In 2001 Eli Yablonovitch co-founded the company Luxtera, which is now a leading commercial developer of silicon photonic products. See also HPCwire. Photonic crystals, manipulators of light, they are alive. They are alive “because they are the physical shape of the action of a living power—of the mind that had been able to grasp the whole of this complexity, to set its purpose, to give it form.” –AR 1957
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 The Fountainhead by Ayn Rand
 Atlas Shrugged by Ayn Rand
Syndicate |
Pressing the 'like' button
Pressing the 'like' button on the Nobel prize in physics post.
Shockley
My parents knew the Shockleys in the late 1930s. I have photos of Shockley paddling a canoe on a lake in upstate New York with my sister sitting up front. My Mother told me his IQ was only in the low 130s (maybe 129) which is amusing considering how much public emphasis he put into IQ later in life. She knew this because the nursery school they shared with their children in Manhattan made a great deal out of collecting IQ info from all the parents, and this got passed around somehow. This meant both my parents blew him out of the water regarding their IQs as they did with me too. (Groan. It's not easy being dumb.) However, I did see him on TV in the very late 1960s or early 1970s and it was obvious he was sharp as a tack brilliant. I personally think real genius tends to be coincidental to very high IQ and most people who have very high IQs aren't really geniuses. Anyway, my Father was of the mind that Shockley really was the sole inventor of the transistor and that Bell Labs made him share the credit and that was the reason he left Bell Labs. My Mother told me, however, still knowing his wife who knew the other wives, that the opposite was true. I've read since that he was a publicity hound and basically stuck his butt into the situation not having done the really important work. What is true for sure is that Shockley was something of an obnoxious person unbalanced by his brains. This was true of my Dad too. I think this too much brain power for personal objectivity is common. I think it was true of Ayn Rand. Edward Teller never could see the world quite right. He thought the country could be blown up in a nuclear war and rebuilt in only a few years or that a "shield was better than a sword" which wasn't true.
--Brant
2009 Nobel
The 2009 Nobel Prize in Physics has been awarded to three scientists for their contributions to revolutionary optical technologies. This year’s prize is to Charles Kao, who led the search for and development of low-loss optical fibers, and to Willard Boyle and George Smith for their invention of the charge-coupled device.
Semiconductor Devices - Power of Mind
Semiconductors and the Information Revolution
Magic Crystals that Made IT Happen
John Orton (Elsevier 2009)
From Chapter 1
“For many people, the run-up to Christmas 1947 probably represented a welcome return to some semblance of peaceful normality following the end of the Second World War hostilities. But at the Bell Telephone Laboratories in Murray Hill, NJ something altogether more significant was in the air. On 16 December Walter Brattain and John Bardeen, senior members of William Shockley’s Solid State Physics Group, observed for the very first time the phenomenon of electronic power gain from their Heath Robinson arrangement of springs and wires, connected to a small piece of germanium crystal. The culmination of two years of concentrated effort, this was the world’s first solid state amplifier and the world was never to be quite the same again. In terms of its long-term impact on human life, the transistor (as soon as it became known) was probably of far greater significance even than the war which had so recently ended—and which had, incidentally, contributed considerably to its development.”
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Starlight
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Photonic Crystal Fibers
for the Kilo-Aperture Optical Spectrograph
for the Gemini Observatory
Astrophotonics: A New Era for Astronomical Instruments
Joss Bland-Hawthorn and Pierre Kern
Thanks for these posts
Thanks for these posts Stephen. I enjoy learning about spintronics and some others, and am glad you're keeping up with amazing new technologies that I may have missed.
Aaron
Spintronics
Putting Electron Spin to Work
“Spintronics”
Sankar Das Sarma
Persistent Spin State
EurekAlert (2009)
“Spintronics: Fundamentals and Applications”
Igor Zutic, Fabian, and Sarma
“Semiconductor Spintronics”
Jaroslav Fabian et al.
The Abyss
You would enjoy, I think, a movie, now of some vintage, but which played on Cable last month, called The Abyss. It has Ed Harris as chief of an experimental, deep-water, oil-drilling rig, and soon-to-be ex of Mary Elizabeth Mastrantonio, the engineer who is the rig's brilliant, and determined designer.
The rig gets commandeered by the Pentagon to mount an emergency rescue and recovery mission for a sunken nuclear submarine. A Hurricane wreaks havoc with the surface installation that serves their power and oxygen-supplies, and all hell breaks loose on every possible front.
There is one scene, in which Harris and Mastrantonio are trapped in a flooding mini-sub, that demands a solution the likes of which I have never seen nor dreamt of in story-telling on any scale! I defy anyone to find a match for it.
The ending is set at right-angles to the literary virtues of the rest of the tale. That is a warning.
If you happened to have missed this, you are in for a treat.
Mindy
Toshihko Baka
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“Slow Light in Photonic Crystals”
Nature Photonics – August 2008
Photonic Crystal Nanolasers: A, B
Applied Physics Letters – 2008
Photonic Crystals and LEDs
Photonic Crystals Improve LED Efficiency
Photonic Crystals Enable Ultrabright LEDs
Photonic Crystal Fibers
“This made me very receptive to the suggestion by Eli Yablonovitch and Sajeev John in 1987 that a full electromagnetic band gap might be created by periodically structuring a high refractive index material to produce a ‘photonic band gap crystal’. Their main interest lay in creating an absence of photonic states in three dimensions, something that Yablonovitch went on to demonstrate experimentally at microwave frequencies. I quickly realized that one might be able to achieve low-loss guidance of light in a hollow fiber core. The challenge would be . . . .”
“Photonic Crystal Fibers: A Historical Account” – Philip Russell
High-Bright White
Charles Hard Townes Award – 2008
Bravo!
Great Engineering Achievements of Last Century
Stephen
Great review. Thanks
Photonic-Crystals and General Relativity
Photonic-crystal fibers are at work in laboratory tests for predicted phenomena of general relativity and quantum field theory taken together.
Science 319
"Fiber-Optical Analogue of the Event Horizon"
Abstract - “The physics at the event horizon resembles the behavior of waves in moving media. Horizons are formed where the local speed of the medium exceeds the wave velocity. We use ultrashort pulses in microstructured optical fibers to demonstrate the formation of an artificial event horizon in optics. We observed a classical optical effect, the blue-shifting of light at a white-hole horizon. We also show by theoretical calculations that such a system is capable of probing the quantum effects of horizons, in particular Hawking radiation.”
Appendix – Wider Explanation
See also this sector of Ulf Leonhardt’s homepage.
Nanocomposite Power Paper
Paper Battery and Supercapacitor
Shocking Sheets - Science News 8/18/07
Further:
"Flexible Energy Storage Devices Based on Nanocomposite Paper,"
V. L Pushparaj, S. M. Manikoth, A. Kumar, S. Murugesan, L. Ci, R. Vajtai, R. J. Linhardt, O. Nalamasu, P. M. Ajayan,
Proceedings of the National Academy of Science USA 104, 13574-13577, (2007).
What is a supercapacitor?
A & B
A Garden of Innovation
Making Silicon Valley
Innovation and the Growth of High Tech, 1930-1970
Christophe Lécuyer (MIT Press 2005)
From the Cover:
“In Making Silicon Valley, Christophe Lécuyer shows that the explosive growth of the personal computer industry in Silicon Valley was the culmination of decades of growth and innovation in the San Francisco-area electronics industry. . . . He explores the formation of Silicon Valley as an industrial district, from its beginnings as the home of a few radio enterprises . . . through its establishment as a center of the electronics industry and a leading producer of power grid tubes, microwave tubes, and semiconductors. He traces the emergence of the innovative practices that made this growth possible by following key groups of engineers and entrepreneurs. He examines the forces outside Silicon Valley that shaped the industry—in particular the effect of military patronage and procurement on the growth of the industry and on the development of technologies—and considers the influence of Stanford University and other local institutions of higher learning.
“Lécuyer argues that Silicon Valley's emergence and its growth were made possible by the development of unique competencies in manufacturing, in product engineering, and in management. Entrepreneurs learned to integrate invention, design, manufacturing, and sales logistics, and they developed incentives to attract and retain a skilled and motivated workforce. The largest Silicon Valley firms—including Eitel-McCullough (Eimac), Litton Industries, Varian Associates, Fairchild Semiconductor, and Intel—dominated the American markets for advanced tubes and semiconductors and, because of their innovations in manufacturing, design, and management, served as models and incubators for other electronics ventures in the area.”
Seeing at Femtosecond
Tracking Light in Photonic Crystal
Blazar
New product from the company co-founded by Eli Yablonovitch:
Blazar, the first commercial silicon-based optical cable.
See here and here.
Lase!
How the Laser Happened
Adventures of a Scientist
Charles H. Townes
Light plus Water
Light plus Water equals Fuel
http://www.chem.vt.edu/chem-dept/brewer/energyresearch.htm
http://web.mit.edu/chemistry/dgn/www/research/e_conversion.html
http://www.nrel.gov/docs/fy06osti/39966.pdf
Dec 07 - Light, Water, Hydrogen
Aug 08 – Storing Solar Energy
Catching More Light
Quantum Photosynthesis
http://www.lbl.gov/Science-Articles/Archive/PBD-quantum-secrets.html
http://www.sciencemag.org/cgi/content/full/sci;316/5830/1462
Thanks for this article
Stephen,
Thanks for this article! Many people don't know just what a marvel solid state and device physics is. If people want to see the true power of this, they should drive down Bowers Avenue in Santa Clara and see hogh technology companies numbering in the middle hundreds on that street alone.
For another true hero, look no farther than former Intel CEO and Chairman Andy Grove. He had a Rand-like biography escaping the Nazis in Hungary as a boy and making his way to the Untied States.
Jim
References
Scientific American
1983 (Nov) “Solid-State Superlattices” –G.H. Dohler
1984 (Aug) “Quasicrystals” –D.R. Nelson
1986 (Oct) “Photonic Materials” –J.M. Rowell
1991 (Nov) “Microlasers” –J.L. Jewell, J.P. Harbison, and A. Scherer
1998 (Mar) “Nanolasers” –P.L. Gourley
2001 (Dec) “Photonic Crystals: Semiconductors of Light” –E. Yablonovitch
2007 (Feb) “Making Silicon Lase” –B. Jalali
Science News
1991 (Nov 2) “Drilling Holes to Keep Photons in the Dark” –I. Peterson
1993 (Sep 25) “A Novel Architecture for Excluding Photons” –I. Peterson
1996 (Nov 16) “Light Gets the Bends in a Photonic Crystal” –C. Wu
1998 (Oct 24) “Crystal Bends Light Hard, Saves Space” –P. Weiss
2003 (Oct 4) “Hot Crystal” –P. Weiss
2005 (Nov 5) “Light Pedaling” –P. Weiss
Nature Photonics
2007 (1:91–92) “Bandgap Engineering: Quasicrystals Enter Third Dimension” –C.T. Chan
Fundamental Papers – Physical Review Letters
1987 (May 18) “Inhibited Spontaneous Emission in Solid-State Physics and Electronics”
–E. Yablonovitch
1987 (Jun 8) “Strong Localization of Photons in Certain Disordered Dielectric Superlattices” –S. John
1989 (Oct 30) “Photonic Band Structure: The Face-Centered-Cubic Case” –E. Yablonovitch and T.M. Gmitter
1990 (Nov 19) “Full Vector Wave Calculation of Photonic Band Structures in Face-Centered-Cubic Dielectric Media” –K.M. Leung and Y.F. Liu
1990 (Nov 19) “Electromagnetic Wave Propagation in Periodic Structures: Bloch Wave Solution of Maxwell’s Equations” –Z. Zhang and S. Satpathy
1990 (Dec 17) “Existence of a Photonic Gap in Periodic Dielectric Structures” –K.M. Ho, C.T. Chan, and C.M. Soukoulis
1991 (Oct 21) “Photonic Band Structure: The Face-Centered-Cubic Case Employing Non-Spherical Atoms” –E. Yablonovitch, T.J. Gmitter, and K.M. Leung
Saw those in Babylon 5
Saw those in Babylon 5 didn't we?