You’ve probably heard of Moore’s Law, which states that transistor count on microprocessors will double every two years or so. What you may not know is that the storage capacity of magnetic hard drives leaves Moore’s Law in the dust: Many types of hard drives have been doubling in capacity every year for the last three years.
According to scientists at leading research institutes like the NEC facility near Princeton, N.J., you ain’t seen nothing yet. New materials and techniques being developed at the lab could greatly expand data-storage capacity, leading to PC hard drives and memory sticks that could store as many as 2000 feature-length films on a single disk or stick in just a few year, and in fact, it’s already happening. The same materials are also used to make cell phones more efficient, automobiles safer, and small-appliance motors less expensive.
As detailed in a report published in a recent issue of Science magazine, NEC researchers have developed new composite materials that exhibit a property they dubbed “extraordinary magnetoresistance,” or EMR. These materials, when applied to the read heads of disk drives, allow for more sensitivity when reading magnetic information on the spinning hard disk. The actual disk platter, then, can be jammed with more information.
Stuart Solin, the lead researcher with the NEC team that published the report, explains that the technology could dramatically increase the potential recording density of magnetic media. “The state of the art current 3.5-inch hard disk has a [recording] density of about 28Gb per square inch,” Solin says. “With our stuff, in the future, we could get to a terabit [1,000Gb] per square inch.”
Solin says these new EMR materials can potentially improve the performance of any given magnetic data system, with possible applications in consumer electronics, wireless devices, even automobile systems such as antilock brakes.
“That’s probably the first place where you’ll see these things hit the market,” he says. “The company that licensed our intellectual property makes sensors for the auto industry–it should show up within about a year or two.”
In fact, to hear Solin tell it, there are magnetic sensors everywhere–each a potential market for this technology. “There are a lot of things that have a multitude of magnetic sensors in them. Our sensors could, in principle, replace them because they’re cheaper and a lot more effective,” he says.
One potential application is in the development of magnetic sensors for cellular phones, Solin says. “For example, with flip phones, there’s a big market for magnetic switches that know when the phone is open.”
Cell phone makers prefer magnetic switches to mechanical switches for reasons of durability, Solin explains. But current magnetic switches tend to interfere with magnetic fields generated by the earpiece microphone. “That means you have to run more current through the earpiece magnet to increase the signal above this interference field,” Solin says. Because EMR materials are more sensitive, they would generate less of an interference field, improving overall efficiency.
The list goes on: “In consumer electronics, there’s a market for 10 billion sensors that are sold to control small motors,” Solin says. “Every disk drive has four or five of these just to run the motors that turn the disk.”
Solin concedes that while EMR technology may be more efficient than current techniques, actually bringing it to market is likely to be a slow process–especially for PC hard drives.
“The people who are doing the conventional technology have a huge amount of investment in this–and it is making money,” Solin says.
Still, many industry observers say that current magnetic storage techniques are limited. Jim Porter, president of the storage industry market research company Disk/Trend, notes that many companies are pursuing advanced magnetic storage technology–including such heavy hitters as IBM, Fujitsu, Hitachi, and Seagate. “A lot of people are working on this because of the expectation that within a few years, we’ll hit the limit of conventional magnetic recording,” Porter says.
Meanwhile, there are many other potential applications for EMR materials. “There’s a huge variety of markets where this can and will have an impact,” Solin says. “We’d like to do the read head thing, too, but I’m realistic about it. Our stuff will probably not be used for read head purposes until the other guys hit a wall. But I’m pretty sure they’re going to hit a wall.”