(a)

(b)

(c)

d

d

Figure 8.1. Schematic representations of nanocomposite materials with characteristic length scale: (a) nanolayered composites with

nanoscalebilayer repeat length ; (b) nanofilamentary (nanowire) composites composed of a matrix with embedded filaments of nanoscale diameter d; (c) nanoparticulate composites composed of a matrix with

embedded particles of nanoscale diameter d.

Figure 8.2. Schematic energy band diagram of GaAs/GaAlxAs1-x quantum well. An electron (represented by its wavefunction ) can be considered

as partially confined in the quantum well of width equal to the GaAs thickness. The barrier height E is equal to the difference in the energies of the bottom of the conduction band Ec for the two layer materials. Ev is the energy of the top of the valence band and Egap is the band gap energy.

Egap for

AlxGa1 xAsEgap for

GaAs

Ec

Ev

E

thickness of GaAs layer

Figure 8.3. Precipitate particles of spacing acting as obstacles to dislocation motion.

hard precipitate particles

dislocation

Figure 8.4. High resolution transmission electron micrograph showing a cross-sectional view of an InAs-GaSb (100) superlattice (Reproduced

with kind permission of M. Twigg.)

Figure 8.5. Scanning electron micrograph of electrodeposited FeCo nanowires (the polycarbonate matrix in which the wires were embedded

has been completely dissolved).

Figure 8.6. Bright field transmission electron micrographs of Ni/SiO2 granular metal films. (From Ref. 29 by permission of Elsevier Science

B.V.)

Figure 8.7. Transmission electron micrographs of binary nanoparticle assemblies. (a) Fe3O4(4nm)-Fe58Pt42 (4nm) assembly; (b) Fe3O4 (8nm)-

Fe58Pt42 (4nm) assembly; Fe3O4 (12 nm)- Fe58Pt42 (4 nm) assembly. (From Ref. 46 by permission of Macmillan Magazines Ltd.)