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Scientists Build Graphene From Scratch, Atom By Atom
MrSeb writes "You've heard of 'designer babies,' the idea that you can customize a baby by altering its DNA, but now a team of researchers from Stanford University and the Department of Energy have meddled around with the very fabric of reality and created the very first 'designer electrons.' The bulk of the universe is made up from just a few dozen elements, and each of these elements is made up of just a few subatomic particles: electrons, protons, neutrons, quarks, and so on. For the most part, the properties of every material — its flexibility, strength, conductivity — is governed by the bonds between its constituent atoms, which in turn dictate a molecule's arrangement of electrons. In short, if you can manually move electrons around, you can create different or entirely new materials. That's exactly what Stanford University has done: Using a scanning tunneling microscope, the team of researchers placed individual carbon monoxide molecules on a clean sheet of copper to create 'molecular graphene' — an entirely new substance that definitely isn't graphene, but with electrons that act a lot like graphene (abstract). It is now possible, then, for scientists to create entirely new materials or tweak existing materials — like silicon or copper, or another important element — to make them stronger or more conductive. Where will this particular avenue lead us?"
Wrong! The bulk of the universe -- about 70% -- is made of dark energy and we have no idea what that's made of. Then there's dark matter -- about 25% (no idea what that's made of either) -- while less than 5% is made of normal, barionic matter (electrons, protons, neutrons, quarks, and so on).
I think the bigger question is, "how would you move this process to a FAB"? I don't think it will happen soon, but it seems to me we would need robotic STMs? Research is continuing... I assume.
Nice generic smaller technology quip, but I think you missed the point of TFA and what the posters you were responding to (hint, they read and understood it). You should actually read it, its more about a change in the understanding of physics than new chips.
I don't think so. The cited and heavily quoted article seems to start with a fundamental misunderstanding of freshman level physics: "the bulk of the universe is made up from just a few dozen elements, and each of these elements is made up of just a few subatomic particles: electrons, protons, neutrons, quarks, and so on". Quarks are not subatomic particles, they are the elemental particles that subatomic particles are made from. In other words your proton is made of quarks. That makes phrases like "meddled around with the very fabric of reality" a bit suspicious. Reading the article confirms this suspicion.
If you look at the second citation, the one from real scientists, they are using phrases like "new nanoscale materials with useful electronic properties". So if you only read the fist citation then yes we are on the verge of star fleet manual type science. However if you the second article we are closer to new fabrication technologies.
The journalist is making it harder to understand what is going on.
IANAP but here's how I understand it thanks to google.
First, 85 tesla have been generated for very short instants in the lab so the article is wrong in saying 60 tesla is higher than ever achieved.
Graphene forms a two-dimensional lattice surface like a chicken wire fence.
For each molecule of graphene a single electron sticks out from the surface.
These electrons are free to hop around to other atoms.
In fact they act just like particles that have no mass and can travel at 1% of the speed of light. These quasiparticles are called massless dirac fermions. A fermion is a particle with certain properties, the nucles of a helium atom being one kind of fermion.
Electrons travelling at relativistic speeds is not earth shattering since that is what happens in gold atoms too. But the point is the electrons are free to sweep through the lattice without hindrance, and that if you can control the way the electrons move, you can control the apparent properties of the quasiparticles.
In 2010 Francisco Guinea in Madrid predicted that stretching graphene along all the axes of it crystal structure will make the electrons act as if subjected to a magnetic field.
http://www.gizmag.com/straining-graphene-creates-strong-pseudo-magnetic-fields/15891/
http://physics.berkeley.edu/research/zettl/pdf/386.Science.329-Levy.pdf
In July 2010 Michael Crommie proved the prediction, by growing bubbles of stretched graphene that stick up like pyramids from the platinum surface they were grown on. The electrons acted as if they were subjected to 300 tesla fields.
This technique works at room temperature.
The paper mentioned by the OP talks about designer Dirac fermions which means that you can create quasiparticles possessing the characteristics you desire by simply moving atoms around so they make electrons move in the way necessary to make the quasiparticles appear to exist. You can thereby freely mess with simulated mass, electrical and magnetic fields, etc. which might be very useful.
http://www.nature.com/nature/journal/v483/n7389/full/nature10941.html
The technique used in the OP experiment is low temperature and nanoscale. But based on Crommie's work it should not be hard to imagine processes in the future that could allow similar structures to be built quickly on a larger scale.
This is an exciting a relatively new field of research apparently but breathless reports using terms like designer babies or designer electrons when it is really designer quasiparticles, and saying that the fabric of reality is being messed with, is just distracting and does not help people who are not prepared to dive into the actual research paper to find out what is going on.
Well it turns out that if the author's article isn't misquoting Manoharan, he actually did claim that the electrons had no mass and were moving at the speed of light. That would be a huge scientific breakthrough if it were true.
As a physicist, I would say that Manoharan was probably spot on, but the journalist failed to understand and relay him correctly. You're correct that "massless electrons moving at lightspeed" is a scientific breakthrough, that's why it was awarded the Nobel prize in 2010.
To explain: in graphene, the dispersion relation becomes a bit funny. See explanation on Wikipedia. This means that electrons behave as if they were massless and moving at the speed of light. They are neither, of course, they just behave as if they are.
Car analogy: if you drive your car on ice covered with water, it will behave as if it had no brakes. It still has brakes, it just behaves as if it didn't.
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