Exciton semiconductors

Epitaxial ItcHNOLOGY for Integrated Circuit Manufacturing Excitons, Semiconductor Lasers Lasers, Optical Fiber Lasers, Solid-State Light Emitting Diodes Metalorganic Chemical Vapor Deposition (MOCVD) Molecular Beam Epitaxy, Semiconductors Optical Amplifiers (Semiconductor) Semiconductor Alloys... 

Gregg BA, Chen SG, Branz HM (2004) On the superlinear increase in conductivity with dopant concentration in excitonic semiconductors. Appl Phys Lett 84 1707-1709... 

Figure Al.3.25. Schematic illustration of exciton binding energies in an insulator or semiconductor.

Even in semiconductors, where it might appear that the exciton binding energies would be of interest only for low temperaPire regimes, excitonic effects can strongly alter tlie line shape of excitations away from the band gap. 

Here, E and s are the band gap energy and the dielectric constant of the bulk semiconductor, and p is the reduced 0 mass of the exciton system, 1/p = + 1/fffi,. The second tenn, proportional to /R, arises from a simple... 

Figure C2.17.11. Exciton energy as a function of particle size. The Bms fonnula is used to calculate the energy shift of the exciton state as a function of nanocrystal radius, for several different direct-gap semiconductors. These estimates demonstrate the size below which quantum confinement effects become significant.

Primary Photoexcitations in Conjugated Polymers Molecular Exciton versus Semiconductor Band Model (Ed. N.S. Sariciftci) World Scientific, Singapore 1997. 

In low-dimensional systems, such as quantum-confined. semiconductors and conjugated polymers, the first step of optical absorption is the creation of bound electron-hole pairs, known as excitons [34). Charge photogcncration (CPG) occurs when excitons break into positive and negative carriers. This process is of essential importance both for the understanding of the fundamental physics of these materials and for applications in photovoltaic devices and photodctcctors. Since exciton dissociation can be affected by an external electric field, field-induced spectroscopy is a powerful tool for studying CPG. 

Nozik AJ (2008) Multiple exciton generation in semiconductor quantum dots. Chem Phys Lett 457 3-11... 

Slightly below the lower edge of the conduction band of a semiconductor are the levels of the exciton, i.e. a state where the charge carriers do not move independently... 

The semiconductor structure is crucial for both electron injection and charge transport after the exciton separation. Meng et al. [35] published a theoretical study focused on the electron injection mechanism in dyad anthocyanine-Ti02 nanowires. 

John O. Dimmock, Introduction to the Theory of Exciton States in Semiconductors B. Lax and J. G. Mavroides, Interband Magnetooptical Effects... 

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