Monday, August 13, 2007

Rewritable Holographic Memory

Continued from page 1

By Amitabh Avasthi

Holographic storage devices in general, Harvey notes, could bridge a growing gap between the capacity of storage devices and the speed with which they access data. As an example, he points out that transferring a 30-gigabyte file comprising a full-length high-definition movie to a computer's hard drive may take 30 to 45 minutes using current technology. Holographic devices have the potential to reduce that time to less than 10 seconds.

Among the people interested in the new development is Liz Murphy, vice president of marketing at InPhase Technologies in Longmont, CO, which has demonstrated a holographic device with a storage density of 500 gigabytes per square inch and has several products in the pipeline. "At least one potential advantage is that it is erasable and rewritable, which is rare among currently available media," Murphy says of the UConn researchers' device. "However, a drawback is that recording is in the red, and blue light is used to erase the recordings."

That's a limitation because "storage density typically increases with shorter wavelengths," she notes, pointing to the progression from CD to Blue-ray/HD-DVD technology. "So limiting use of the bacterial media to red wavelengths will make it less attractive to use for high-density data-storage applications."