The world's smallest graphene modulator was unveiled recently by researchers at the National Science Foundation (NSF) Nanoscale Science and Engineering Center at the University of California-Berkeley. The research team, led by professor Xiang Zhang, claimed its breakthrough will someday allow smartphones to download entire movies in a matter of seconds.
The world's smallest graphene modulator uses electrical signals to switch an laser on and off for faster, smaller, cheaper optical communications. Source: UC Berkeley
Today, optical modulators are used to speed communications by using electrical signals to switch a laser on and off for long-haul communications between systems. However, high-speed optical communications is migrating to short-haul communications and someday may even be used by mobile devices to quicken the transfer of large files.
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