200 nm 1 nm 0.1 nm 0.1 nm (3D)

Superlattice

For an e at room temperature, 0.026 eVE kT

de Broglie wavelenth, 8 nm.2

h hp mE

If the layer thickness is comparable with then

quantum effects are important (quantum confinement).

HeterostructureIn some cases two different not only crystallize in the same manner but also have same lattice constants.

Both the materials grow together as a single crystal with two parts

The interface of these two materials in called a heterojuction

A heterojunction is an interface in a crystal of two different materials with the same lattice constant

When a heterojunction is repeated at regular intervals, we get the heterostructure.

Quantum structures and DOS

Applications are based on

1. Peculiar properties

Eg. Gold nanoparticles used as inorganic dye into glass and as low temperature catalyst

2. Huge surface area

Photoelectrochemical cells, sensors

3. Small size

Molecular Electronics and Nano electronics

Single molecules, Chem FET, ion selective FET (ISFET)

Nanobots

Nano medicine, nano robots

Biology

Nano biotech, DNA analysis

Catalysis by Gold nanoparticles in oxidation

Bandgap engineered quantum devices

Quantum well devices, quantum dot devices

Nanomechanics

Eg. Atomic Force Microscope (AFM)

Carbon nanotube emitters

Generates monochromatic electron beams of 7mm in diameter

Sensors, scanning probe tips, Li batteries

Photoelectrochemical Cells

High efficient conversion, large surface area

Photonic crystals and Plasmon waveguides

Waveguides and high-resolution spectral filters