Science and Technology of Nanostructures Physics 805, Fall 2009 F. J. Himpsel Syllabus, Info, Lecture Notes :

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

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

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

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

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

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

5 nm Optimum Hard Disk Reading Head

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

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

The Physicist’s View: Fundamental Length Scales Quantum Electric Magnetic Quantum Well: Quantum Well Laser Capacitor: Single Electron Transistor Magnetic Particle: Data Storage Media a = V 1/3 Consider devices operating at room temperature. Their energy levels have to be separated by more than the thermal energy k B T = 25 meV. Convert this energy scale to a length scale by fundamental constants. Charging Energy 2e 2 /  d Spin Flip Barrier ½ M 2 a 3 Energy Levels 3h 2 /8m l 2 d E1E1 E0E0 l l 3 nm

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

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

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

Knitting with Polymers

In Pursuit of the Ultimate Storage Medium : 1 Bit = 1 Atom 10  m 10 nm CD-ROM Silicon Surface Density x nm Track

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

250 Terabit/inch 2 Year 2038 When will we be down to atoms ? Using Moore's Law...

Nanotechnology: A Moving Target nanoLithography nano + bio Directed Assembly nano + bio + info Self-assembly

The Madison Discovery Institutes (Nano + Bio + Info)

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