Slashdot Mirror
Programmable Matter: The New Alchemy
Anonymous Kamath writes "IEEE Spectrum recently published an interview with aerospace-engineer-turned-science-fiction-author Wil McCarthy who's just written his first non-fiction book "Hacking Matter: Levitating Chairs, Quantum Mirages and the Infinite Weirdness of Programmable
Atoms" proposing the application of quantum dot technology on a large scale
thereby allowing one to control properties of materials at will. Another science fiction author laid down the principles of geostationary satellite communication
half a century ago."
registration/sucks
Really, I registered a free account with this combo.
'He was a dreamer, a thinker, a speculative philosopher... or, as his wife would have it, an idiot.' - Douglas Adams
The New Alchemy
Could semiconductor technology do for material science what it has for computing?
Imagine a solid wall that, as the occasion demands, becomes completely transparent or transforms on one side into a giant video screen while the other side becomes either a solar panel or a heat pump that cools a room on a hot day. This is the promise of programmable matter--and it could make the technology revolution wrought by semiconductors to date look like a warm-up for the main act.
The idea of programmable matter began to seep into the popular consciousness in recent years through the works of aerospace-engineer-turned-science-fiction-author Wil McCarthy [right], who dubbed the new material wellstone in novels like The Collapsium (Del Rey, 2000). Now McCarthy has written his first nonfiction book about programmable matter, Hacking Matter: Levitating Chairs, Quantum Mirages and the Infinite Weirdness of Programmable Atoms. Associate Editor Stephen Cass talked to him about this bleeding-edge technology and how McCarthy himself is helping to transform science fiction into science fact.
What is programmable matter?
Programmable matter is fundamentally a solid-state technology--something that can change its optical, physical, magnetic, or electrical behavior without any moving parts except for electrons or photons. In that sense, there are certain things now that already qualify as programmable matter, like an LCD [liquid-crystal display] screen. This is an assembly of devices, but you can also look at it as carefully arranged material that has the interesting property of changing color under electrical stimulation. By adjusting quantum dots instead of pixels, you can make artificial atoms and adjust a lot more than just the color of the material.
What are quantum dots and how do you use them to make artificial atoms?
A natural atom is a particular means for confining electrons--the positively charged nucleus gathers electrons around it and doesn't let them escape. By confining the electrons, you force them to behave as standing waves. And those standing waves are responsible for nearly all the chemical, electrical, and optical properties that we associate with atoms.
But you don't have to have an atomic nucleus to get that sort of behavior out of electrons; you just have to confine them in a small space. There are a lot of ways to do this. One way is to use the standard techniques of semiconductor chip design to create junctions that will herd electrons into an area of choice, known as a quantum dot. Once confined, the electrons will form a structure known as an artificial atom. With artificial atoms, unlike natural atoms, there is no reason why you can't pump electrons in and out and change their characteristics dynamically, making them programmable.
But if these programmable atoms are buried in a semiconductor substrate, how do they interact with anything? How do you make the entire material behave like it's made out of, say, gold?
With programmable atoms in a substrate, what you are really doing is creating controlled impurities--dopant atoms--so the properties of your semiconductors are going to be very important in determining the final properties of the programmable substance. You can get a very high level of doping with a properly designed quantum dot array and overwhelm the normal behavior of the semiconductor. You can never ignore the fact that the semiconductor is there, but you can change its properties almost beyond recognition.
So would you have to combine different types of artificial atoms to end up with a material whose net behavior is like that of gold?
Probably. An artificial atom of gold-- pseudo-gold--is almost certainly going to be a lot larger than an atom of natural gold. One consequence of this is that its absorption and reflection spectrum will be redshifted, because the electrons are less tightly bound so they will be at lower energies. So even if you could somehow have atoms of pseudo-gold without any substrate, they'd be
The New Alchemy
Could semiconductor technology do for material science what it has for computing?
Imagine a solid wall that, as the occasion demands, becomes completely transparent or transforms on one side into a giant video screen while the other side becomes either a solar panel or a heat pump that cools a room on a hot day. This is the promise of programmable matter--and it could make the technology revolution wrought by semiconductors to date look like a warm-up for the main act.
The idea of programmable matter began to seep into the popular consciousness in recent years through the works of aerospace-engineer-turned-science-fiction-author Wil McCarthy [right], who dubbed the new material wellstone in novels like The Collapsium (Del Rey, 2000). Now McCarthy has written his first nonfiction book about programmable matter, Hacking Matter: Levitating Chairs, Quantum Mirages and the Infinite Weirdness of Programmable Atoms. Associate Editor Stephen Cass talked to him about this bleeding-edge technology and how McCarthy himself is helping to transform science fiction into science fact.
What is programmable matter?
Programmable matter is fundamentally a solid-state technology--something that can change its optical, physical, magnetic, or electrical behavior without any moving parts except for electrons or photons. In that sense, there are certain things now that already qualify as programmable matter, like an LCD [liquid-crystal display] screen. This is an assembly of devices, but you can also look at it as carefully arranged material that has the interesting property of changing color under electrical stimulation. By adjusting quantum dots instead of pixels, you can make artificial atoms and adjust a lot more than just the color of the material.
What are quantum dots and how do you use them to make artificial atoms?
A natural atom is a particular means for confining electrons--the positively charged nucleus gathers electrons around it and doesn't let them escape. By confining the electrons, you force them to behave as standing waves. And those standing waves are responsible for nearly all the chemical, electrical, and optical properties that we associate with atoms.
But you don't have to have an atomic nucleus to get that sort of behavior out of electrons; you just have to confine them in a small space. There are a lot of ways to do this. One way is to use the standard techniques of semiconductor chip design to create junctions that will herd electrons into an area of choice, known as a quantum dot. Once confined, the electrons will form a structure known as an artificial atom. With artificial atoms, unlike natural atoms, there is no reason why you can't pump electrons in and out and change their characteristics dynamically, making them programmable.
But if these programmable atoms are buried in a semiconductor substrate, how do they interact with anything? How do you make the entire material behave like it's made out of, say, gold?
With programmable atoms in a substrate, what you are really doing is creating controlled impurities--dopant atoms--so the properties of your semiconductors are going to be very important in determining the final properties of the programmable substance. You can get a very high level of doping with a properly designed quantum dot array and overwhelm the normal behavior of the semiconductor. You can never ignore the fact that the semiconductor is there, but you can change its properties almost beyond recognition.
So would you have to combine different types of artificial atoms to end up with a material whose net behavior is like that of gold?
Probably. An artificial atom of gold-- pseudo-gold--is almost certainly going to be a lot larger than an atom of natural gold. One consequence of this is that its absorption and reflection spectrum will be redshifted, because the electrons are less tightly bound so they will be at lower energies. So even if you could somehow have atoms of pseudo-gold without any substrate,
Technoli
http://www.spectrum.ieee.org/WEBONLY/resource/apr0 3/book.html
ok... I got it from some search engine...
From an earlier post:
"It should be noted that Tsiolkovsky was talking about geosynchronous orbits around 1900, and radio engineer George O. Smith wrote about communication satellites in "QRM Interplanetary" in 1942. However, Smith's communication satellites/stations were generally placed at Trojan points in order to give line-of-sight between planets around the sun (hence the name of the novel/story collection "Venus Equilateral"). Of course, no one made a movie of one of Smith's books, so everyone forgets him..."
I have nothing against Arthur C. Clarke, but credit should go where it is due. And when life on Europa or diamonds on Jupiter are discovered, THEN it will be a prediction. Until then, it's called "speculation".
Thought you guys might find this interesting as well, since the page is gone....
t ml
http://pm.bu.edu/
http://www.wilmccarthy.com/pmfaq.htm
http://www.wired.com/wired/archive/9.10/atoms.h