Quote :

"A computer simulation of the optical nano antenna that Harvard researchers have fabricated. Consisting of two gold-coated nano rods separated by a 30-nanometer gap, the antenna can focus light from a commercial laser to a spot just 40 nanometers wide. It could be used to write terabytes, rather than gigabytes, of data to a CD or DVD. (Credit: Ertugrul Cubukcu)"

http://www.technologyreview.com/read_article.aspx?id=17504&ch=infotech

Quote :

"A new nano-optical device can focus laser light tighter than traditional optics, which could lead to higher-density data storage. By Kate Greene As gigabytes of movies, pictures, audio, and text fill up more and more CDs and DVDs, there's clearly a need for better ways to save more data. A research team at Harvard University has developed a technique that could help to significantly boost the capacity of conventional optical discs. They've fabricated a nano antenna--built directly onto an inexpensive, off-the-shelf laser--that focuses light to a much smaller spot size than is possible with even the best traditional lenses, potentially enabling more bits to be written onto an optical disc. The storage capacity of a disc increases as the wavelength of light used to write data to it decreases; CDs are written and read using light with a wavelength of 780 nanometers, DVDs use 650 nanometers, and HD-DVDs and Blu-ray discs use 405 nanometers. Wavelengths shorter than 405 nanometers would require light sources far too expensive for consumer electronics. The problem is that conventional lenses can only focus light to half their wavelength, a physical barrier called the diffraction limit. The Harvard researchers sidestepped this limit, however, by abandoning traditional optics in favor of nano-optical techniques. "We can get around the wavelength limitation by using an antenna," says Ken Crozier, assistant professor of electrical engineering at Harvard. The team of Crozier, Federico Capasso, professor of applied physics at the university, and graduate students Eric Kort and Ertugrul Cubukcu designed the optical antenna to focus light from a commercial laser (with a wavelength of 830 nanometers) to a spot size of 40 nanometers. With this resolution, "you'd be able to pack more than three terabytes [3,000 gigabytes] worth of data onto something the size of a CD," Crozier estimates. That's enough to hold more than 300 feature-length movies. By comparison, a dual-layer HD-DVD or Blu-ray disc can hold 30 gigabytes or 50 gigabytes, respectively. The antenna consists of two gold-coated nano rods, separated by a 30-nanometer-wide gap, according to Crozier. When light from the laser hits the nano rods, it applies a force to the electrons in the gold, nudging them out of place. The electrons don't stay displaced for long, however, and are pulled back toward their original position. But they overshoot it, Crozier says, and bounce back out of place, oscillating "like a mass on a spring." These oscillating electrons affect the tiny gap between the nano rods. If you took a snapshot of the antenna, Crozier says, you'd see that positive charges collect on one side of the gap, and negative charges on the other. The nano rods and gap act as a tiny capacitor--with opposite charges on opposite sides of the gap--that effectively concentrates the energy from the laser light into a spot about the size of the gap. This spot maintains its size to about 10 nanometers away from the antenna before it starts to spread out. Although the 10-nanometer gap is minuscule, researchers could build a new type of optical reading and writing head using the technology, suggests Crozier. The magnetic storage industry, he points out, works with a similarly small gap between the head and medium. Using nano antennas to focus optical light is not an entirely new idea, Crozier says, but their work, published in Applied Physics Letters, is the first time an antenna has been integrated directly onto a laser. This offers an advantage in production because the light source and antenna are in one package. "It's extremely compact and easier to use because alignment with the laser and the antenna is all done in fabrication," he says. There's a lot of research activity to reduce the spot size of light, but it's especially attractive to the data storage industry, says Bae-Ian Wu, a research scientist in the Research Laboratory of Electronics at MIT. Using a nano antenna is just one way to gain "super resolution smaller than the wavelength of light." But, he says, the Harvard researchers work "is very good in the sense that they are doing optical experiments to back up their theory, while some papers are only in the realm of theory." The Harvard scientists, he adds, "just did it." Crozier says his team is exploring fabrication techniques that can further decrease the spot size to 20 nanometers. They're also exploring alternatives to the gold metal that currently coats their nano rods. Silver, for instance, could focus light more efficiently than gold at the wavelengths used by the consumer electronics industry. "

9/15/2006 10:24:10 AM

9/15/2006 10:26:11 AM

what are you so about?

9/15/2006 10:31:13 AM

wow, that level of storage per disc is insane. imagine having something like the entire Library of Congress on one CD, next to a PDF copy every unclassified government document ever produced in the history of the country, with a few gigs left over for whatever else...

and then of course there's all the stuff that could get packed onto video game CDs/DVDs

[Edited on September 15, 2006 at 10:58 AM. Reason : l33t]

9/15/2006 10:55:12 AM

^ Dude, you forgot the pr0n.

9/15/2006 11:03:08 AM

My guess, 5-10 years before it hits the home-consumer market. By that point, hard drives will most likely have increased enough in size that the technology will just be "catching up".

9/15/2006 1:19:50 PM

^that's pretty unlikely.

the latest breakthrough in hard drive tech is perpendicular recording, which is nice + all and makes for higher capacity, but nowhere near the level that this would offer.


I wonder how much space all the pr0n on the interweb would take up.

9/15/2006 1:53:34 PM

Quote :

"the latest breakthrough in hard drive tech is perpendicular recording, which is nice + all and makes for higher capacity, but nowhere near the level that this would offer."

i thought holographic recording was the next level?

9/15/2006 3:19:08 PM

when was the last time you saw a holodisc for sale? at least perpendicular recording comes relatively cheaply on seagate drives

i imagine this is just like every other advancement...we hear about it now, forget about in a week and NEVER HEAR ABOUT IT AGAIN, just like holodiscs

9/15/2006 3:44:23 PM

Quote :

"Ertugrul Cubukcu"

9/15/2006 5:00:19 PM

This technology could help make holo-recording a reality. There are (is?) prototype holocube drives, but they are gigantic.

9/15/2006 5:21:03 PM

http://en.wikipedia.org/wiki/Hard_disk#1990s

Fun reading on a Friday night. Check out the Seagate's research into nanotube-lubricated HDDs. 7.5 terrabytes in a 3.5" drive they are estimating.

9/15/2006 10:04:18 PM

THINK OF THE PORNO

9/16/2006 3:17:30 PM

i wonder how much porno has ever been created, in TB

9/16/2006 3:22:35 PM