Nanotechnology:Data Storage Activity and Other Topics

Nanotechnology:Data Storage Activity and Other Topics

Mark Tuominen Professor of Physics

Science Saturday, Sept. 12, 2009: Part 2

First, a bit more on Self-Assembly

Langmuir-Blodgett FilmMust control movablebarrier to keep constantpressure

multiple dips -multiple layers

solid

liquid

QuickTime™ and a decompressor

are needed to see this picture.

Shape Matters!

QuickTime™ and a decompressor

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Shape Matters!

Tobacco Mosaic Virus

wisc.edu

nih.gov

Magnetic Data StorageA computer hard drive stores your data magnetically

Disk

N S

direction of disk motion

“ Write”Head

0 0 1 0 1 0 0 1 1 0 _ _

“ Bits” ofinformation

NS

“ Read”Head

Signalcurrent

Binary Representation of Data

one bit “ 1” or “0” only 2 choices

two bits 00, 01, 10, 11 4 choices

three bits 000, 001, 010, 011,100, 101, 110, 111

8 choices

n bits has 2n choices

For example, 5 bits has 25 = 32 choices...more than enough to represent all the letters of the alphabet

Character "SS"codea 00001b 00010c 00011d 00100e 00101f 00110g 00111h 01000i 01001j 01010k 01011l 01100

m 01101n 01110o 01111p 10000q 10001r 10010s 10011t 10100u 10101v 10110w 10111x 11000y 11001z 11010

Binary representationof lower case letters

5-bit "Super Scientist" code:

ex: k = 01011

0 1 0 1 1

S

N

S

N

S

N

N

S

N

S

OR

(Coding Activity: Use attractive and repulsive forces to "read" the magnetic data!)

Nanotechnology and Nanoscience: People from diverse fields working

together to provide new solutions to problems facing society

• Physics• Chemistry• Biology• Materials Science• Polymer Science• Electrical Engineering• Chemical Engineering• Mechanical Engineering• Medicine• And others

• Electronics• Materials• Health• Chemical• Environmental• Energy• Food• Aerospace• Automotive• Security• Forest products

Nanoscale Biology:A couple examples

20 m

20 m

25 nm

8 nm

Up to 1 m

QuickTime™ and a decompressor

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QuickTime™ and a decompressor

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Jenny Ross, UMass, Physics

Targeted Cancer Therapy

Cancer Therapy

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tumor

gold nanoshells

Halas group, Rice Univ.

www.sciencentral.com/articles/view.php3?article_id=218392390

targeted therapy: hyperthermic treatment

www.nano.gov/html/news/SpecialPapers/Cancer

Another Example:Solar Energy

Solar Cells

Konarka

Benefit: Sun is an unlimited source of electronic energy.

Electric Solar Cellsp-n junction interface

cross-sectional view

n-type silicon

p-type silicon

+

-

Sunlight

Voltage “load”

CurrentThe electric power produced is proportional to the area of the solar cell

- - - -- - - - + + + ++ + + + 0.5 Volt

Nanostructured Solar Cells

+

-

Sunlight

Voltage “load”

CurrentMore interface area - More power!

How to measure nanoscale objects?(One example: The Atomic

Force Microscope)

(Atomic Force Microscope) "Optical Lever" Principle

To determine amplification factor, use the concept of similar triangles

laser pointer

"Optical Lever"

y1

x1

y2

x2

€

y2x2=y1x1

€

y2 =x2x1y1

For example, if the laser pointer is 2" long, and the wall is 17' (204") away,

€

y2 =204

2y1 ≈100y1 Motion amplified

by 100 times!

.

"Optical Lever" for Profilometry

cantilever

laser

.

"Optical Lever" for Profilometry

cantilever

laser

Long light path and a short cantilever gives large amplification

.

Analysis: Distance Multiplier

cantilever

laser

Long light path and a short cantilever gives large amplification

d1

d2

L1

L2

pivotpoint

The distance amplification d2/ d1 is proportional to L2/ L1

Atomic Force Microscope

Diblock

AFM image

µmCopolymer

tip

Ato

mic

For

ce M

icro

scop

eA

tom

ic F

orce

Mic

rosc

ope

AFM Cantilever Chip AFM Instrument Head

Laser Beam Path Cantilever Deflection

A Message for Students

Nanotechnology will change practically every part of our

lives. It is a field for people who want to solve technological challenges facing

societies across the world

NSF Center for Hierarchical Manufacturing

Research Education Outreach

A Center on Nanomanufacturing at UMass

www.umass.edu/chm(including videos on nanoscience)