Quantum heterostructure

From ArticleWorld

Quantum heterostructures are epitaxially-grown heterojunctions of a substrate with movement of charge carriers (electrons or holes) restricted and subjected to ‘quantum confinement’. This phenomenon refers to semiconductors, in which a set of discrete energy levels, where the carriers can stay, is formed. Energy levels in a quantum heterostructure are closely packed; this close packing is sharper than what it is in structures of other types.

Quantum heterostructure – development and application in modern technology

Quantum heterostructures are important for the fabrication of light emitting diodes, which are used in a number of ways. Various types of embedded systems require LEDs as informative indicators. Remote controls used for TVs and VCRs use infrared-emitted LEDs. The advantages of LEDs using quantum heterostructures mean an increased presence in various technological applications, possibly even as replacements to the incandescent bulbs. Diode lasers are also manufactured using quantum heterostructure. It was in the 1960s when Russian physicist Zhores Alferov succeeded in using heterostructures to prepare faster and vastly improved transistors that this concept began to be applied further. It was realised that under the correct and suitable characteristics, electrons and holes in the semiconductor can be combined to generate light. Alferov’s laser was the first practical example of a quantum heterostructure laser. The concept of quantum heterostructures is used in satellite communication, mobile-telephone networks and high-speed Internet connections. This technology has made it possible to reproduce digitally recorded sound and for retailers and security officials to track items.