Whereas average properties derived from constituent materials describe macroscopic objects, as they usually obey the laws of classical mechanics, a mesoscopic object, by contrast, is affected by thermal fluctuations around the average, and its electronic behavior may require modeling at the level of quantum mechanics.
However, at the mesoscopic level, the wire's conductance is quantized: the increases occur in discrete, or individual, whole steps.
During research, mesoscopic devices are constructed, measured and observed experimentally and theoretically in order to advance understanding of the physics of insulators, semiconductors, metals, and superconductors.
The subdiscipline has dealt primarily with artificial structures of metal or semiconducting material which have been fabricated by the techniques employed for producing microelectronic circuits.
The quantum confinement effect can be observed once the diameter of the particle is of the same magnitude as the wavelength of the electron's wave function.
In addition, quantum confinement effects consist of isolated islands of electrons that may be formed at the patterned interface between two different semiconducting materials.
[6] In the mesoscopic regime, scattering from defects – such as impurities – induces interference effects which modulate the flow of electrons.
The experimental signature of mesoscopic interference effects is the appearance of reproducible fluctuations in physical quantities.
For example, the conductance of a given specimen oscillates in an apparently random manner as a function of fluctuations in experimental parameters.