A Casimir chip that exploits the vacuum energy
July 31, 2012
Casimir forces on parallel plates (credit: Wikipedia Commons)
University of Florida researchers have have developed a way to keep objects flat enough to measure the strange Casimir force, which pushes two parallel conducting plates together when they are just a few dozen nanometers apart, Technology Review Physics arXiv Blog reports.
They carved a single device out of silicon that is capable of measuring the Casimir force between a pair of parallel silicon beams, the first on-chip device capable of doing this.
The device consists of one fixed beam and another moveable one attached to an electromechanical actuator. Other shapes should be possible to manufacture too. “This scheme opens the possibility of tailoring the Casimir force using lithographically defined components of non-conventional shapes,” the researchers say.
So instead of being hindered by uncontrollable Casimir forces, the next generation of microelectromechanical devices should be able to exploit them, perhaps to make stictionless bearings, springs and even actuators.
The set-up of the experiment and device. (a) A simplified schematic (not to scale) of the beam, movable electrode and comb actuator supported by four springs, with electrical connections. The current amplifier provides a virtual ground to the right end of the beam. The suspended and anchored parts of the comb actuator are shown in dark and light colors respectively. The separation d between the beam and the movable electrode was controllably reduced so that the Casimir force can be detected. (b)-(e) Scanning electron micrographs of the entire micromechanical structure (b) and close-ups of: the doubly clamped beam (c), zoomed into the white dashed box in (b); the comb actuator (d) and the serpentine spring (e). (Credit: J. Zou, et al.)
Verios (credit: FEI)
Microscopes for viewing nanoscale devices
Monitoring these kind of ultra-small nanoscale devices requires special microscopes, such as the scanning electron microscope (SEM), which images a sample by scanning it with a beam of electrons. (The Casimir device image above is an example of an SEM image).
An SEM can produce very high-resolution images of a sample surface, revealing details less than 1 nanometer in size (the size of small biomolecules).
FEI has just announced the new Verios XHR SEM, which provides the sub-nanometer resolution and enhanced contrast needed for precise measurements in materials science and advanced semiconductor manufacturing applications.
An even higher-resolution microscope is the transmission electron microscope (TEM), with a resolution of 0.5 Angstroms (.05 nm). An example of a TEM image is shown in this news item today on graphene layers.
Another type of nanoscale microscope is the atomic force microscope (AFM). It has several advantages over the 2D SEM; it provides a 3D surface profile, for example. It also has disadvantages: it doesn’t allow for large scanned images, and is very slow, for example.
Nonetheless, AFMs are vital tools in nanotechology, and nanoHUB.org has just announced a two-part, web-based course covering the principles and practice of atomic force microscopy.
(Credit: nanoHUB/Purdue University)
The course content has been condensed from the original 15-week (1 semester) course offered at Purdue University into two, five-week online courses.
Fundamentals of Atomic Force Microscopy, Part 1: Fundamental Aspects of AFM will be taught from August 27 to September 28, 2012.
Fundamentals of Atomic Force Microscopy, Part 2: Dynamic AFM Methods provides an in-depth treatment of dynamic mode AFM. Part 2 will be taught from October 15 to November 16, 2012.
The courses require basic familiarity with topics usually covered in a two-semester college course in introductory physics. A working knowledge of both integral and differential calculus is assumed.
Comments (5)
by Bri
The casamir effect is so indicative of the yin and yang. Even in the black there is white. Even in a total vacuum, or total darkness, there is light. The jumping Jesus rate is getting so high, to study is like becoming rip van winkle
by Bri
The most legal fun?ooooo kkkkkkk. I literally don’t have the time. Love to know. I’ll wait till the matrix downloading gets perfected. I’ve got almost one hundred orchids, and where as most people wouldn’t love it like I do, I’d take that example alone over calculus. Aiming a gun, or archery is amazing too, but I’d rather play music, with or without someone else. Now that’s a rush that’s almost indescribable. Then there’s all that bonobo stuff. I’m very intrigued by calculus and mathematics, I wish it was more fasil for me, bbbbuuuuttttt, I’ll get over it. Now about this casimir effect. That is quite an interesting topic! Where do these “virtual” particle come from? More important, if it can move a physical object, where do they go????
by Gorden Russell
You had me until you said, “A working knowledge of both integral and differential calculus is assumed.”
by Editor
Hey, calculus is the most legal fun there is, and it’s visually instinctive. It’s all here: http://www.khanacademy.org/math/calculus?k .
by SpottedMarley
I’m actually in the middle of re-learning all of my math’s starting with algebra and up to and including calculus at Khan Academy. Can’t wait to get to Calculus! I had forgotten so much, even just with algebra. Their site is absolutely amazing and, in my opinion, is how most people will “go to school” in the future.