Science and Technology of Nanostructures Physics 805, Fall 2009 F. J. Himpsel

1. Science and Technology of Nanostructures Physics 805, Fall 2009 F. J. Himpsel Syllabus, Info, Lecture Notes: http://uw.physics.wisc.edu/~himpsel/Nano/lectures.htm

2. Nanotechnology in our Daily Life Iridescent car paint: Based on interference colors (like a butterfly, no bleaching after 5 years Miami)

3. Gate Source Drain Nanotechnology on our Desktops Transistor Hard Disk Sensor Medium Gate oxide 4 nm Well 6 nm Switching layer 5 nm Magnetic grain 10 nm

4. Quantum Well Laser: Designing the Perfect Trap 6 nm : Optimum Thickness

5. Nanocrystals Quantum effect: Crystal size determines the color (blue-shifted when smaller)

6. When does silicon cease to be silicon? The band gap of silicon nanoclusters GaAs Bulk Silicon 3 nm : Gap begins to change

7. Transistor Gate Oxide Power consumption by a leaky gate oxide: A show-stopper for silicon technology?

8. Hard Disk Reading Head 5 nm Optimum

9. How small is a Nanometer ? Each panel 10x smaller Each time something different Two more steps to reach one nanometer 125 nm Hewlett-Packard molecular memory

10. Universe (largest length) 1027 The Sun is a billion times larger than a human, and a nanometer is a billion times smaller. 10–35 Planck Length (smallest length) 10–3 mm 10–6 m 10–9 nm

11. l Consider devices operating at room temperature. Their energy levels have to be separated by more than the thermal energy kBT = 25 meV.Convert this energy scale to a length scale by fundamental constants. The Physicist’s View: Fundamental Length Scales Quantum Electric Magnetic Quantum Well:Quantum Well Laser Capacitor:Single Electron Transistor Magnetic Particle:Data Storage Media E1 E0 a= V1/3 d Energy Levels3h2/8ml2 Charging Energy2e2/d Spin Flip Barrier ½M2a3 l< 7 nm d< 9 nm a> 3 nm

12. Biological Length Scales in the Nanometer Range DNA Virus (TMV) 3.4 nm pitch 10 base pairs 300 nm 2 nm 11 nm 18 nm

14. Molecular Motor This end is attached to another muscle fiber, pulling it along. Driven by the reaction ATP  ADP + Energy Walker = myosin, kinesin Rail = actin, tubulin = part of a muscle fiber Linear Motor (Muscle) Vale and Milligan, Science 288, 88 (2000)

15. Life-like Structures at a Surface Wieczorek et al., Website Electrolyte Artificial Membrane Rotary generator = Rotary motor in reverse Converts ADP to ATP Powered by proton pump Water Solid substrate Bacteriorhodopsin as light-driven proton pump Cornell et al., Nature 387, 580 (1997); Tanaka & Sackmann, Phys. Stat. Sol. A 203, 3452 (2006).

16. Knitting with Polymers

18. In Pursuit of the Ultimate Storage Medium : 1 Bit = 1 Atom Silicon Surface CD-ROM 1.6nm Track 10 m 10 nm Densityx 1000000

19. Speed versus Density Shot noise speed limit DNA Density limit: 5x4 cell = 20 atoms/bit • Speed is sacrificed as density increases (less signal per bit) • Densityis limited by coupling between bits (range ~4 atoms)

20. When will we be down to atoms ? Using Moore's Law ... 250 Terabit/inch2 Year 2038

21. Nanotechnology: A Moving Target nano Lithography nano + bio Directed Assembly nano + bio + info Self-assembly

22. The Madison Discovery Institutes (Nano + Bio + Info)

23. A business model for Nanotechnology? Start with niche applications, then break into mass markets. "Disruptive Technologies" Clayton Christensen Harvard Business School