By Peter Weiss
Gangsters break someone’s arm to deliver a message, leaving a powerful impression that may never go away. Now, a team of Chinese and U.S. scientists finds that roughing up organic molecules also can leave an enduring, though small, memory. In this case, however, some reverse strong-arming can quickly wipe out that memory.
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Today’s CD-ROMs squeeze 100 million bits into each square centimeter of recording surface. In the Feb. 21 Physical Review Letters, Hongjun Gao of the Chinese Academy of Sciences in Beijing and his colleagues report writing and erasing data in minute dots. These dots could potentially be crammed together to encode information a million times more densely than CD-ROMs do and top even hard disks by a factor of nearly 100,000. However, the lab accomplishment remains far from commercial realization, the experimenters caution.