Carrier Transport in Low-Dimensional Semiconductors
Carrier transport in semiconductors with reduced dimensions is determined by the low-dimensional density of states. In two-dimensional systems such as quantum wells and superlattices, the carrier mobility is highly anisotropic. Parallel to the barriers it may exceed the bulk value by far in a two-dimensional electron gas at low temperature. Perpendicular to the interfaces, carriers have to penetrate the barriers and the mobility is low. Tunneling through thin barriers is an important process; it is enhanced when matched with quantized energy levels and leads to negative differential resistance. In one-dimensional quantum wires, ballistic transport occurs and the conductance gets quantized. Transport through a zero-dimensional quantum dot is affected by charging with single electrons, giving rise to a Coulomb blockade with zero conduction at certain bias values.
KeywordsBallistic transport Bloch oscillations Carrier mobility Coherent tunneling Conductance quantization Coulomb blockade Coulomb diamond High-field domain Landauer-Büttiker formalism Landauer formula Negative differential resistance One-dimensional transport Resonant tunneling diode Sequential tunneling Transmission coefficient Tunneling Quantum-cascade laser Quantum wire Single-electron tunneling Subband Two-dimensional electron gas Wannier–Stark ladder Zero-dimensional transport
- Lyssenko V, Leo K (2011) Bloch oscillations and ultrafast coherent optical phenomena. In: Bhattacharya P, Fornari R, Kamimura H (eds) Comprehensive semiconductor science and technology, vol 2: Physics and fundamental theory. Elsevier BV, Amsterdam, pp 343–399Google Scholar
- Nixon JA, Davies JH, Baranger HU (1991) Conductance of quantum point contacts calculated using realistic potentials. Superlattice Microstruc 9:187Google Scholar