Controlling Atoms

Many readers of this site will know that a large amount of research in physics is devoted toward miniaturization, specifically at an atomic level, referred to as nanotechnology. Engineering feats at this level require an intense amount of precision and also innovation to develop technology that can manipulate matter on such small scales. Two such innovations working together have come out of the University of Texas at Austin (with, as always, collaborations with other institutions).

The first is an "atomic coilgun," which runs a beam of particles through a solenoid (see "WiTricity - Power Without Wires" for more on solenoids). The beam of particles are going "against" the magnetic force, so it is slowing the atoms in the beam down until they eventually become trapped.

The calculations would need to be very carefully prepared, or else the atoms would slow down within the solenoid, come to a stop, and begin accelerating in the other direction! A process called "single-photon cooling" (the second innovation) corrects of this by creating a "wall" of laser light. When the atoms come to a stop, therefore, they will not backslide down the solenoid if this one-way wall of light is blocking them!

The individual atoms are therefore isolated by being slowed with the atomic coilgun, and then trapped by the single-photon cooling techniques. Previous photon cooling techniques have been impressive, but have typically worked for only some atoms - typically those at the lower end of the periodic table. According to University of Texas at Austin physicist Mark Raizen, this will work on most atoms in the periodic table.

Sources:

• ScienceDaily.com - Controlling Most Atoms Now Possible
• Physics Review Letters - " Stopping Supersonic Beams with a Series of Pulsed Electromagnetic Coils: An Atomic Coilgun" and " Single-Photon Atomic Cooling" abstracts
• TG Daily - Atomic coilgun developed, capable of slowing paramagnetic atoms and molecules for research
• University of Texas at Austin - Atomic Coilgun Used to Slow and Stop Atoms
• About Physics - Force to Move an Atom
• About Physics - Nanotechnology Overview