Scientists at the University of Alberta have demonstrated a new data storage technique that stores zeroes and ones by the presence (or absence) of individual hydrogen atoms. The resulting storage density is an unparalleled 1.2 petabits per square inch – 1,000 times greater than current hard disk and solid state drives, and 100 times greater than Blu-rays.
Ultra-high density storage devices aren't new, but they usually come with serious drawbacks that make them impractical in the real world. In the past, scientists have managed to store bits of digital information in a single molecule and even a single atom, but only in systems that had to operate at cryogenic temperatures, near vacuum pressure, or both. By contrast, this latest technology is designed work at room temperature and is expected to be able to preserve information without errors for over 500 years.
The researchers, led by PhD student Roshan Achal and physics professor Robert Wolkow, built on a technique previously developed by Walkow that used the tip of a scanning tunneling microscope (STM) to remove or replace individual hydrogen atoms resting on a silicon substrate.
The inconceivably small dimensions (a hydrogen atom is only half a nanometer in diameter) allow for an astounding data storage density of 1.1 petabits (138 terabytes) per square inch. By comparison, a Blu-ray disk can "only" store about 12 terabits of data in the same area (one hundredth the data density), while both traditional magnetic hard drives and solid-state drives store somewhere in the region of 1.5 terabits per square inch (a thousandth of the density). This development, says Achal, could allow you to store the entire iTunes library of 45 million songs on the surface of a US quarter-dollar coin.
Achal and his team demoed the technology by creating a 192-bit cell, which they used to store a simple rendition of the Super Mario Bros video game theme song. To show the rewrite capabilities, the scientists also created an 8-bit memory cell which they used to store the letters of the alphabet one by one, represented via their respective ASCII code.
Unfortunately, writing speeds still leave something to be desired. According to the accompanying paper, writing each 8-bit ASCII code took between 10 and 120 seconds, which isn't exactly practical for today's consumer products. However, the fact that this technology is built on silicon and uses materials that can easily interface with existing semiconductor technology bodes well for the future automation of the process.
In fact, Wolkow is confident that atom-scale fabrication is on the verge of becoming commercially viable. His spinoff company, Quantum Silicon Inc., is working on developing classical and quantum computers that would operate at room temperature and which, because of their atomic scale, would benefit from much reduced power consumption.
The study appears in the latest issue of the journal Nature Communications and is further illustrated in the video below.