US Patent 7409375 - Optical memory formed from nanotube cells

http://www.freepatentsonline.com/7408835.html

Nantero has taken the lead in developing nanotube based memory over the past few years based on using the nanotubes as nanomechanical switches. However, a few companies are attempting to develop alternative approaches to nanotube memory. This patent from STMicroelectronics teaches a hybrid mechanical-optical memory system based on the use of a nanoactuator to "write" a carbon nanotubes geometrical structure in a memory cell and an optical sensor to read the structure. Claim 14 reads:

14. A memory, comprising:

a memory cell comprising nanotubes and operable to store a data value related to the bandgap energy of the cell, wherein the bandgap energy of the cell is related to the shapes of the majority of the nanotubes;

a nanoactuator operable to write the data value to the memory cell; and

an optical energy sensor operable to read the data value from the memory cell.