https://doi.org/10.1351/goldbook.08861
Effect occurring if at least one dimension of a structure is comparable to the de Broglie wavelength of the electron-hole pair and the motion of charge carriers is thus quantized by the structure boundary.
Notes:
- A material composed of quantum-size structures exhibits electronic and optic properties different from those of bigger structures. A quantum size effect can be thus detected as an alteration of electronic and optical properties of a solid when reducing its particle size down to nanometer scale.
- Based on the confinement dimensionality the following quantum-size objects are distinguished:
- quantum dot: three-dimensional confinement; example: nanoparticles of CdS;
- quantum wire: two-dimensional confinement; example: carbon nanotubes;
- quantum well: one-dimensional (linear) confinement; example: nanoscale layer of GaAs sandwiched between two layers of a wide-band-gap semiconductor such as AlAs.