Finance

A quantum dot is a semiconductor whose excitons ar imprisoned in all three spatial dimensions. Consequently, such materials progress to electronic properties in edgeediate between those of bulk semiconductors and those of discrete molecules.[1][2][3] They were disc over at the beginning of the 1980s by Alexei Ekimov[4] in a glass matrix and by Louis E. Brus in colloidal solutions. The term quantum dot was coined by Mark Reed.
Researchers have studied quantum dots in transistors, solar cells, LEDs, and diode lasers. They have also investigated quantum dots as agents for medical checkup imaging and hope to use them as qubits.
Stated simply, quantum dots are semiconductors whose electronic characteristics are closely related to the size and incarnation of the individual crystal. Generally, the smaller the size of the crystal, the large the great deal gap, the greater the difference in zipper between the highest valence band and the lowest conduction band becomes, therefore more energy is needed to excite the dot, and concurrently, more energy is released when the crystal returns to its resting state. For example, in fluorescent dye applications, this equates to higher frequencies of cleared emitted after innervation of the dot as the crystal size grows smaller, resulting in a color shift from red to blue in the light emitted.



In addition to such tuning, a main service with quantum dots is that, because of the high level of control possible over the size of the crystals produced, it is possible to have very precise control over the conductive properties of the material.[5] Quantum dots of different sizes can be assembled into a gradient multi-layer nanofilm.
The ability to tune the size of quantum dots is advantageous for many applications. For instance, larger quantum dots have a greater spectrum-shift towards red compared to smaller dots, and manifest less pronounced quantum properties. Conversely, the smaller particles allow one to concern advantage of more subtle quantum effects....If you want to get a full essay, order it on our website: Orderessay



If you want to get a full essay, wisit our page: write my essay .