Disk vendors are the heroes of storage
Disk vendors don’t get much respect from Wall Street, but they do the heavy lifting that makes affordable massive storage possible. And it looks like the hits will just keep on coming.
Hitachi Global Storage Technology is announcing a five-platter terabyte 3.5″ hard drive; and I just heard about a technique for building diode lasers that produce a dot size so small that a one terabyte optical CD is possible.
One TB in hand vs one TB in bush
Hitachi GST is to be congratulated on achieving the one TB milestone. According to the this morning’s Wall Street Journal (subscription required) HGST did it with five platters.
Seagate will ship a four platter one TB drive later this year that should also be cheaper since it won’t have an extra platter and two more read/write heads. Decisions, decisions.
I saw in a TechRepublic blog this morning that a breakthrough in diode laser focusing is making it possible to build cheap diode lasers that can read and write dots that are smaller than the wavelength of the light they generate. This is huge. In a nanotechnology sense.
If you’ve been following the chipmaker’s march to smaller feature sizes over the last few decades, you’ve noted that they’ve been bumping up against this seemingly insurmountable problem: as feature sizes get smaller, they’ve had to go to shorter – now deep ultra-violet – wavelengths to produce those small features. Work has been going on with x-ray lithography for years, but the chip industry just hasn’t wanted to give up their tried-and-true optical technology.
What the physicists have created, as summarized on a Harvard website, is a nanoparticle-based optical antenna. They say:
Optical antennas are single or coupled metallic nanoparticles in which optical excitation of surface plasmons can produce very high intensities in the optical near field. . . . This design leads to a large intensity enhancement localized in the gap between the latter.
In other words, the optical antenna creates a very focused laser beam. How focused? It creates a dot with “subwavelength spatial resolution” meaning an 800 nanometer wavelength laser can produce a dot of a “few tens of nanometers”, or about a 100x improvement. Typically, the dot size is a ~5x multiple of the light’s wavelength.
Using this technique, the researchers invented
a photonic device which consists of a resonant optical antenna integrated on the facet of a commercial diode laser.
The scientists believe these antennae can be fabricated, using standard techniques, on current diode lasers.
They see applications for the technology in two storage areas – optical disks and heat-assisted magnetic recording – among other applications.
Optical disks you know about. Heat-assisted magnetic recording (HAMR) heats small magnetic particles on a platter to make them easier to magnetize reliably, helping overcome the dreaded superparamagnetic limit. Smaller laser spot means smaller magnetic particles can be heated and magnetized.
The StorageMojo take
Assuming the technology can be commercialized – and that is no doubt at least five years away – we’ve added at least another decade of 40-50% areal density improvements to disk storage, both optical and magnetic.
It almost seems like yesterday when the first one GB 3.5″ hard drive – from Maxtor, I think – came to market in the early ’90s. So in the last ~15 years we’ve had a 1000x increase in capacity – 10x every five years.
Thus in 2022, we’ll have 3.5″ disks with a one petabyte capacity, if such a clumsy form factor is still in use. How about a 160 TB notebook drive? And Blu-ray will be a forgotten antique.
Comments welcome, of course. BTW, the first hard drive I ever had on a PC was a 5 MB Seagate. Whoa!