PowerPoint - LeTourneau University

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Fall 2008 Seminar Schedule

September

11 Nanoscience: when small is big

Gary DeBoer , LeTourneau University

25 Liquid crystals: when rocks are as hard as water

-Michael Korn and students, LeTourneau University

October

2 Three Major Challenges in Cosmology and Particle Physics, and Their Possible Solutions in String/M-Theory

Anzhong Wang, Baylor University, Department of Physics

16 Beauty and the Clot: A Paradigm for Elegance in Design

- Pierre Neuenschwander, University of Texas Health Center, Tyler, TX

30 LEGS

- Karen Rispin and students, LeTourneau University, Department of Biology

November

6 TBA

- T. Howard Stone, J.D. LL.M, University of Texas Health Center, Tyler, TX

13 Of Mice and Matricins

Andrew Baggett, LeTourneau University, Department of Chemistry and Physics

20 Ever Consider Graduate School? (6:00 - 7:00 pm)

- Caroline Gattic, graduate school representative

December

4 History of the elements

-Jim Marshall, University of North Texas

Opinions expressed by the speakers are their own and should not be identified with an official position of LeTourneau University.

Nanotechnology

when

small

is

BIG

Presented by: Gary DeBoer

September 11, 2008

Glaske C101

11:00 am

Some definitions

• Quantum wells, 1 D < 100 nm,

– surfaces, semi conductors

• Quantum wires, 2 D < 100 nm,

– carbon nanotubes

• Quantum dots, 3 D < 100 nm,

– bucky balls

– Nanocrystals

I like to point out that this Armchair Quantum Wire endeavor is a "Faith-

Based Research Project". It is based on the faith that when God made the

Nanotechnology, when

small

is the

BIG

thing

Armchair Quantum Wire, and to do it with great cleanliness and efficiency. If so, then all I have to do is go find that path that God put there in the beginning. With the vast knowledge we have assembled over the years of physics and chemistry, and the sensational new instruments that are now available, we ought to be able to find that path pretty quickly.

My short two years at Hope starting as a freshman in 1961 were immensely important to me. I went to chapel, studied religion, and attended church more than I had ever done before, and was with people who took to these issues seriously. I valued that greatly back then. Recently I have gone back to church regularly with a new focus to understand as best I can what it is that makes Christianity so vital and powerful in the lives of billions of people today, even though almost 2000 years have passed since the death and resurrection of

Christ.

Although I suspect I will never fully understand, I now think the answer is very simple: it's true. God did create the universe about 13.7 billion years ago, and of necessity has involved Himself with His creation ever since. The purpose of this universe is something that only God knows for sure, but it is increasingly clear to modern science that the universe was exquisitely fine-tuned to enable human life. We are somehow critically involved in His purpose. Our job is to sense that purpose as best we can, love one another, and help Him get that job done. http://www.hope.edu/pr/pressreleases/content/view/full/7309

Rick Smalley

http://cnst.rice.edu/

Household

The most prominent application of nanotechnology in the household is self-cleaning or

“easy-to-clean” surfaces on ceramics or glasses. Nanoceramic particles have improved the smoothness and heat resistance of common household equipment such as the flat iron .

Optics

The first sunglasses using protective and antireflective ultrathin polymer coatings are on the market. For optics, nanotechnology also offers scratch resistant surface coatings based on nanocomposites. Nano-optics could allow for an increase in precision of pupil repair and other types of laser eye surgery.

Textiles

The use of engineered nanofibers already makes clothes water- and stain-repellent or wrinkle-free. Textiles with a nanotechnological finish can be washed less frequently and at lower temperatures. Nanotechnology has been used to integrate tiny carbon particles membrane and guarantee full-surface protection from electrostatic charges for the wearer. Many other applications have been developed by research institutions such as the Textiles Nanotechnology Laboratory at Cornell University

Cosmetics

One field of application is in sunscreens. The traditional chemical UV protection approach suffers from its poor long-term stability. A sunscreen based on mineral nanoparticles such as titanium dioxide offer several advantages. Titanium oxide nanoparticles have a comparable UV protection property as the bulk material, but lose the cosmetically undesirable whitening as the particle size is decreased.

http://www.nanotech-now.com/current-uses.htm

A plastic nanocomposite is being used for "step assists" in the GM Safari and Astro

Vans. It is scratch-resistant, light-weight, and rust-proof, and generates improvements in strength and reductions in weight, which lead to fuel savings and increased longevity. And in 2001, Toyota started using nanocomposites in a bumper that makes it 60% lighter and twice as resistant to denting and scratching. http://www.nanotech-now.com/current-uses.htm

Wilson Double Core tennis balls have a nanocomposite coating that keeps it bouncing twice as long as an old-style ball. Made by InMat

LLC , this nanocomposite is a mix of butyl rubber, intermingled with nanoclay particles, giving the ball substantially longer shelf life.

Thus far, the only company among the big boys to convert research into tangible products is Wilson, which offers three drivers, a fairway wood, four balls and even a golf bag made using nano-materials. http://www.nanotech-now.com/current-uses.htm

Microfuel cell cell phones using nanotech in the membrane of the fuel cell for better fuel cell performance

The new Chevy Volt, using nanophosphate electrode technologies for faster recharge with lithium ion batteries.

Principle of Raman Spectroscopy

SERS Nanowire Antenna Arrays

O.J. Glembocki, Code 6880, Naval Research Laboratory laser

Raman finger print

Highly directional

Raman Scattering laser

The status quo: Surface enhanced Raman scattering

• incoherent process

• light scatters in all directions

Nanowire hot spots

Phased arrays result in coherent and highly directional radiation

• Coupled nanowires have highly directional SERS hot spots reducing

4 p scattering.

• Arrayed nanowires can act just like phased array antennas.

MAIN ACHIEVEMENT:

• Use theoretical EM simulations to determine the best configuration of nanowires geometries and array parameters to produce coherent SERS.

• Develop nanowire fabrication techniques that will enable coherent SERS.

• Determine the limitations of coherent SERS in relation to directionality

HOW IT WORKS:

• Theory predicts that closely spaced parallel nanowires exhibit highly directional plasmonic coupling. Arrayed nanowires will produce coherency and high directionality.

• Nanowire arrays, with precise spacing control, defined by e-beam lithography and grown by

VLS vapor growth will be produced to maximize the effect of plasmonic coupling and light channeling to produce coherent SERS.

ASSUMPTIONS AND LIMITATIONS:

• Limitations are that the SERS antenna arrays will be limited to very specific wavelengths.

• We can achieve design parameters that will extend from UV to IR wavelengths

• Assumption that reproducible nanowires arrays can be fabricated with appropriate geometries and metal coverages.

Raman or fluorescence fingerprint

A vehicle for inducing coherency and directionality in SERS and fluorescence.

Nanowire based antenna arrays that combine plasmonics and photonics

Nanowires arrays that induce coherency and directionality in light scattering processes such as

SERS and fluorescence

Understanding of SERS based arrays will advance future capabilities in standoff sensor technologies.

atoms from vapor

VLS Growth

SEM

100nm

InAs

NWs

HRTEM droplet catalyst

20nm

• Semiconductor atoms supplied by vapor

• Metal droplet (patterned dots) act as catalyst

• forms liquid-eutectic with semiconductor atoms

S. Prokes (NRL) Au tip

• Super-saturation is reached  atoms ppt out  NW growth begins

R~4nm

R. Bass (NRL)

Diameter of the nanowire is related to the size of the gold catalyst put down on the silicon.

Larger particles of gold begin to behave like films of gold.

Perpendicular nanowires can be grown in arrays

Need to coat the wires with Au, Ag, or Ni

Dramatization

Shady Sharka

Brilliant Harvard graduate

Dog lover

No patience for fools

Lovely Lena

Postdoc

Originally from Russia

Mama Mahdu

George Mason graduate student

Originally from India

Chucky Charles

Faculty Fellow from

Howard University

Originally from

Trinidad

Dashing and Daring DeBoer

LeTourneau University Professor

Originally from Iowa

Nanotechnology, when

small

is the

BIG

thing

Manipulation at the nanolevel

Drexler

Quantum mechanical properties of nano dimensioned things

Rick Smalley

http://www.crnano.org/whatis.htm

TRUE

FALSE

Nano = 10 -9

Rick Smalley won Noble prize in

1985

Nanotechnology takes advantage of quantum mechanical phenomena

The NRL is in Washington DC

Mama Mahdu disappeared

Lovely Lena was a KGB-CIA intelligence agent

Shady Sharka was misappropriating federal funds

Nanobots could turn the world to gray goo?

LeTourneau has a nanoscience/technology class?

Where are we going?

What of genetic engineering?

Cyborging?

Should we go there?

How to balance benefit and risk?

How do we decide?

Is there a CHRISTIAN response?

Who can we talk to about starting a nanoscience/technology class?

Acknowledgements

Sharka Prokes, NRL advisor, and senior scientist

Orrest Glemboki, NRL senior scientist

Lena Mazeina, Post Doc at NRL

Mahdu Srinivasa, Graduate Student and office mate

The LU Players:

Shady Sharka ….. Swingle

Lovely Lena ………Blumentritt

Chucky Charles ….Taylor

Dashing DeBoer …Baggett

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