Post on 15-Jan-2016
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 Physics16 Beauty and the Clot: A Paradigm for Elegance in Design - Pierre Neuenschwander, University of Texas Health Center, Tyler, TX30 LEGS- Karen Rispin and students, LeTourneau University, Department of BiologyNovember 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 representativeDecember 4 History of the elements-Jim Marshall, University of North TexasOpinions expressed by the speakers are their own and should not be identified with an official position of LeTourneau University.
Nanotechnology
when small is BIGPresented 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
Nanotechnology, when small is the BIG thing
Quantum mechanical properties of nano dimensioned things
Rick Smalley
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 universe he wired into the laws of physics and chemistry a path to make this 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
HouseholdThe 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.OpticsThe 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.TextilesThe 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 UniversityCosmeticsOne 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
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.
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.
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 ArraysO.J. Glembocki, Code 6880, Naval Research Laboratory
Understanding of SERS based arrays will advance future capabilities in standoff sensor technologies.
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:
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.
• 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.
The status quo: Surface enhanced Raman scattering
• incoherent process
• light scatters in all directions
STA
TU
S Q
UO
Raman finger print
laser
NEW
IN
SIG
HTS
Phased arrays result in coherent and highly directional radiation …
• Coupled nanowires have highly directional SERS hot spots reducing 4 scattering.
• Arrayed nanowires can act just like phased array antennas.
Nanowire hot spots
EN
D-O
F-P
HA
SE G
OA
L
Nanowires arrays that induce coherency and directionality in light scattering processes such as SERS and fluorescence
Nanowire based antenna arrays that combine plasmonics and photonics
QU
AN
TIT
ATIV
E IM
PA
CT
A vehicle for inducing coherency and directionality in SERS and fluorescence.
Highly directionalRaman Scattering
laser
Raman or fluorescence fingerprint
VLS Growth
• Semiconductor atoms supplied by vapor• Metal droplet (patterned dots) act as catalyst • forms liquid-eutectic with semiconductor atoms• Super-saturation is reached atoms ppt out NW growth
begins
nanow
ire
metal-droplet catalyst
semiconductor atoms from vapor
R~4nm
R. Bass (NRL)
InAs NWs
Au tip
SEM
HRTEM
S. Prokes (NRL)
20nm
100nm
0
50
100
150
200
0 50 100 150 200
Ga2O
3 nanowire diameter
vs gold colloid diameter
Gold Colloid (nm)
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 arraysNeed 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
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?
TRUE
FALSE
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?
AcknowledgementsSharka 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