Most data storage devices we currently use are, at their core, two-dimensional. Sure, a hard drive might have multiple platters, but the data storage takes place on a flat surface. Even an optical drive is effectively a single surface that holds data. At the City College of New York, they are experimenting with storing data in three dimensions using lab-grown diamonds and LASERs.
Usually, diamonds that have few flaws are more valuable. But in this application, the researchers exploit the flaws to store information. Optical memory that uses a volume instead of a surface isn’t exactly new. However, it is difficult to use these techniques in a way that is rewritable.
Diamonds are a crystalline structure of carbon atoms. Sometimes, though, a carbon atom is missing from the structure. That’s a vacancy. Another defect is when a nitrogen atom replaces a carbon atom. Sometimes a vacancy occurs next to a rogue nitrogen atom and that causes an NV (nitrogen vacancy) center.
It turns out these NV centers are exploitable in several ways ranging from magnetic resonance detection to quantum mechanics experiments. The NV centers can trap an electron, but can also be forced to release a trapped electron. This allows you to treat an NV center with or without an electron as a binary one or zero.
A green LASER can inject an electron into an NV center. A red LASER at low power can determine if an electron is present. At higher powers, the red LASER will eject an electron from an NV center if it is present. If the diamond is in total darkness, the memory state will persevere “virtually forever” according to the researchers (we guess diamonds really are forever).
Of course, the LASER beams are larger than the single-atom defects, but the researchers actually use that to their advantage. By controlling the duration of the LASER pulse, a particular number of NV centers can be charged. That allows a single pulse to store or read multiple bits of data. For example, if the volume contained four NV centers, the volume could represent two bits of information. Since the diamonds are created in a lab, the concentration of NV centers is deterministic.
Currently, the device can store data at a density that exceeds a DVD by about 100 times. However, they are working on ways to get even more dense storage.
We’ve seen glass storage before. You have to wonder if this has applications with 3D ICs, as well.
Photo Credit: [Siddharth Dhomkar] and [Jacob Henshaw] CC BY-ND
I swear they were talking about this 5 years ago for other crystals, and since then we’ve had tech that promises higher density than best possible from single bond dislocations.
However, if you want to write something in stone, I guess this is it.
This is useless research. Everybody should know that the most theoretically efficient way of storing information is using holography. If you analyse under a microscope the interference pattern recorded in an optical hologram you will see the information is actually stored volumetrically.. There is research already trying to exploit this [1].
PS: I am not affiliated with In-Phase.
[1] https://en.wikipedia.org/wiki/Holographic_data_storage
Zardoz….here we come.
Or Stargate I guess.
I read the paper, and some interesting things to note:
-The medium is light sensitive, it needs to re-write the area around where it sets bits, to prevent it from erasing over time.
-I also couldn’t find the pixel density (pixel because they were using grey scale images, to detect loss level) to see what they mean with 100 times a dvd (single sided? Double sided? Single Layer? Dual Layer? HD-DVD?) to determine bit density.
Nice technology and hope that it progresses. I am thinking now of the storage in Hitchhikers Guide to the Galazy.
Makes data destruction easier, a third blu-ray diode (or other effective wavelength) turns your plot to take over the world into a puff of CO2 and smoke.
It sounds like significant amounts of error correction will have to be built into the storage protocol since diffraction affects more than one node at a time.
Think you can get the gist of previous state of the art here…
https://en.wikipedia.org/wiki/Holographic_data_storage
Fast permanent data destruction, add liquid oxygen and burn :D
Or just flash it with a flashlamp.
Their might be some way to reconstruct the data. The flash may knock electrons into voids in a sufficiently deterministic manner to reconstruct the data. Physicial destruction is the only way to be sure when your life or lives of your countrymen are at stake, even with magnetic & conventional solid state storage.
Besides, where’s the fun in that?
That’s an excellent idea. The flash contains both pump and probe wavelengths, and the peak power far exceeds the power of the lasers used to write / read the data. You would end up with a random mix of binary data. Flash it twice just to be sure.
I used to hear about such development and wonder when they would arrive to the public. Then when they didn’t I assumed it failed to pan out. But nowadays I’m wondering if they actually make storage devices that use all that stuff and it’s just kept behind closed doors for NSA use and such. Or alternatively if it’s killed after a payoff off to not disturb the existing market. That makes sense because some of those technologies had working prototypes so you wonder where it went.
I think the “working prototype” tended to fill half a room though.
The flash chips in SSDs are pretty 3D. 48 or more layers of cells (vertically stacked) is pretty common now.
That’s 3D in the same way a hard drive platter stack is 3D. It is layers of effectively 2D storage. The diamond and hologram memory actually stores bits all through its volume.
Maybe I missed something but, if the entire crystal stores the information, what’s to say when the information is read back, its in the same order of sequence?
Slow down, slow down, we still haven’t figured out why come the bits on spinning disk drive don’t get dizzy.