1. 10 GB 2001 20 GB 2002 40 GB 2004 80 GB 2006 160 GB 2007 Data Storage. Example: Advancement of the iPod Hard drive Magnetic data storage Uses nanotechnology!

2. NANOMAGNETS: Magnets are used to store data ? Magnet with unknown magnetic state Current N S 0 S N 1

3. Magnetic Data Storage A computer hard drive stores your data magnetically Disk NS direction of disk motion Write Head 0010100110__ Bits of information NS Read Head Signal current

4. Scaling Down to the Nanoscale Increases the amount of data stored on a fixed amount of real estate ! Now ~ 100 billion bits/in 2, future target more than 1 trillion bits/in 2 25 DVDs on a disk the size of a quarter, or all Library of Congress books on a 1 sq ft tile!

5. Hard Disk Drives - a home for bits Hitachi

6. Improving Magnetic Data Storage Technology The UMass Amherst Center for Hierarchical Manufacturing is working to improve this technology Granular Media Perpendicular Write Head Soft Magnetic UnderLayer (SUL) coil Y. Sonobe, et al., JMMM (2006) 1 bit CHM Goal: Make "perfect" media using self-assembled nano-templates Also, making new designs for storage

7. nanoporous template nanowires in a polycarbonate filter nanowires in a diblock copolymer template Electrodeposited Nanowires in a Nanoporous Polymer Template (Mask) 1x10 12 wires/in 2

8. Binary Representation of Data one bit1 or 0 only 2 choices two bits00, 01, 10, 11 4 choices three bits 000, 001, 010, 011, 100, 101, 110, 111 8 choices n bits has 2 n choices For example, 5 bits has 2 5 = 32 choices... more than enough to represent all the letters of the alphabet

9. Binary representation of lower case letters 5-bit "Super Scientist" code: ex: k = 01011 0 1 011 S N S N S N N S N S OR (Coding Activity: Use attractive and repulsive forces to "read" the magnetic data!)

10. NEW! Multi-State Representation of Data Disk Write Head Read Head == 0 1 direction of disk motion 1032 0 1 2 3 "CLUSTERS"

11. M = -3M = -1M = +1M = +3 3-Nanomagnet Cluster Imaged with a MFM (Magnetic Force Microscope) Just accomplished summer 2007 in the CHM!

12. "Multi-state" representation of lower case letters 1032 What is the word?